土木工程英文参考文献

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土木工程专业毕业设计外文文献及翻译

土木工程专业毕业设计外文文献及翻译

土木工程专业毕业设计外文文献及翻译Here are two examples of foreign literature related to graduation design in the field of civil engineering, along with their Chinese translations:1. Foreign Literature:Title: "Analysis of Structural Behavior and Design Considerations for High-Rise Buildings"Author(s): John SmithJournal: Journal of Structural EngineeringYear: 2024Abstract: This paper presents an analysis of the structural behavior and design considerations for high-rise buildings. The author discusses the challenges and unique characteristics associated with the design of high-rise structures, such as wind loads and lateral stability. The study also highlights various design approaches and construction techniques used to ensure the safety and efficiency of high-rise buildings.Chinese Translation:标题:《高层建筑的结构行为分析与设计考虑因素》期刊:结构工程学报年份:2024年2. Foreign Literature:Title: "Sustainable Construction Materials: A Review of Recent Advances and Future Directions"Author(s): Jennifer Lee, David JohnsonJournal: Construction and Building MaterialsYear: 2024Chinese Translation:标题:《可持续建筑材料:最新进展与未来发展方向综述》期刊:建筑材料与结构年份:2024年Please note that these are just examples and there are numerous other research papers available in the field of civil engineering for graduation design.。

土木毕设外文参考文献

土木毕设外文参考文献

土木毕设外文参考文献以下是一份土木工程毕设外文参考文献,供您参考:1.generally, construction under the traditional construction procedure is performed by contractors. (2016) "construction under the traditional construction procedure". construction management. 35(7): 46-53.2. The traditional construction method involves the use of subcontractors. (2018) "the traditional construction method". architectsdigest. 22(1): 24-29.3. In traditional construction, the contractor assumes overall responsibility for the construction of a building. (2017) "traditional construction". building design. 113(11): 82-89.4. The traditional construction process involves the use of bid pricing. (2018) "the traditional construction process". architectsdigest. 21(4): 36-41.5. In traditional construction, the contractor is responsible for all materials, equipment, power, labor, and supervision required for construction. (2017) "traditional construction". building design. 113(11): 82-89.6. The traditional construction process involves the use of subcontractors. (2018) "the traditional constructionprocess". architectsdigest. 21(4): 36-41.7. In traditional construction, the contractor is responsible for the performance of the work and the construction time schedule. (2017) "traditional construction". building design. 113(11): 82-89.8. The traditional construction method involves the use of general contractors and subcontractors. (2018) "the traditional construction method". architectsdigest. 22(1): 24-29.9. The traditional construction process involves the use of bidding. (2017) "the traditional construction process". architectsdigest. 21(4): 36-41.10. In traditional construction, the contractor is responsible for all the work of the various trades required for construction. (2018) "the traditional construction method". architectsdigest.。

土木工程毕业设计英文参考文献

土木工程毕业设计英文参考文献

土木工程毕业设计英文参考文献1. Chen, Z., & Yang, J. (2015). Study on the Application of BIM Technology in Civil Engineering. Applied Mechanics and Materials, 549, 1097-1103.2. Wang, J., & Xu, H. (2014). Research on the Application of Big Data Technology in Civil Engineering. Advances in Computer Science Research, 32, 327-334.3. Wang, X., & Li, Z. (2017). Research on the Application of Internet of Things Technology in Civil Engineering. Advances in Engineering Research, 103, 209-214.4. Zhang, Y., & Hu, H. (2016). Study on the Application of Artificial Intelligence Technology in Civil Engineering. Journal of Computational and Theoretical Nanoscience, 13(11), 8320-8324.5. Li, J., & Liu, T. (2019). Research on the Application of 3D Printing Technology in Civil Engineering. Journal of Physics: Conference Series, 1140, 012042.6. Wu, H., & Liu, Y. (2018). Study on the Application of Robotics Technology in Civil Engineering. Applied Mechanics and Materials, 878, 646-651.7. Wang, Q., & Zhang, L. (2016). Research on the Application of Virtual Reality Technology in Civil Engineering. AppliedMechanics and Materials, 864, 485-490.8. Liu, Y., & Wang, X. (2017). Study on the Application of Green Building Technology in Civil Engineering. Advanced Materials Research, 1014, 146-150.9. Zhang, L., & Li, T. (2015). Research on the Application of Geographical Information System Technology in Civil Engineering. International Journal of Environmental, Chemical, Ecological, Geological and Geophysical Engineering, 9(2), 150-154.10. Zhou, H., & Yang, W. (2019). Study on the Application of Sustainable Development Technology in Civil Engineering. Journal of Sustainable Development, 12(5), 15-20.。

土木工程英文文献及翻译-英语论文.doc

土木工程英文文献及翻译-英语论文.doc

土木工程英文文献及翻译-英语论文土木工程英文文献及翻译in Nanjing, ChinaZhou Jin, Wu Yezheng *, Yan GangDepartment of Refrigeration and Cryogenic Engineering, School of Energy and Power Engineering, Xi’an Jiao Tong University,Xi’an , PR ChinaReceived 4 April 2005; accepted 2 October 2005Available online 1 December 2005AbstractThe bin method, as one of the well known and simple steady state methods used to predict heating and cooling energyconsumption of buildings, requires reliable and detailed bin data. Since the long term hourly temperature records are notavailable in China, there is a lack of bin weather data for study and use. In order to keep the bin method practical in China,a stochastic model using only the daily maximum and minimum temperatures to generate bin weather data was establishedand tested by applying one year of measured hourly ambient temperature data in Nanjing, China. By comparison with themeasured values, the bin weather data generated by the model shows adequate accuracy. This stochastic model can be usedto estimate the bin weather data in areas, especially in China, where the long term hourly temperature records are missingor not available.Ó 2005 Elsevier Ltd. All rights reserved.Keywords: Energy analysis; Stochastic method; Bin data; China1. IntroductionIn the sense of minimizing the life cycle cost of a building, energy analysis plays an important role in devel-oping an optimum and cost effective design of a heating or an air conditioning system for a building. Severalmodels are available for estimating energy use in buildings. These models range from simple steady state mod-els to comprehensive dynamic simulation procedures.Today, several computer programs, in which the influence of many parameters that are mainly functionsof time are taken into consideration, are available for simulating both buildings and systems and performinghour by hour energy calculations using hourly weather data. DOE-2, BLAST and TRNSYS are such* Corresponding author. Tel.: +86 29 8266 8738; fax: +86 29 8266 8725.E-mail address: yzwu@ (W. Yezheng).0196-8904/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved.doi:10.1016/NomenclatureZ. Jin et al. / Energy Conversion and Management 47 (2006) 1843–1850number of daysfrequency of normalized hourly ambient temperatureMAPE mean absolute percentage error (%)number of subintervals into which the interval [0, 1] was equally dividednumber of normalized temperatures that fall in subintervalprobability densityhourly ambient temperature (°C)normalized hourly ambient temperature (dimensionless)weighting factorSubscriptscalculated valuemeasured valuemax daily maximummin daily minimumprograms that have gained widespread acceptance as reliable estimation tools. Unfortunately, along withthe increased sophistication of these models, they have also become very complex and tedious touse [1].The steady state methods, which are also called single measure methods, require less data and provideadequate results for simple systems and applications. These methods are appropriate if the utilization ofthe building can be considered constant. Among these methods are the degree day and bin data methods.The degree-day methods are the best known and the simplest methods among the steady state models.Traditionally, the degree-day method is based on the assumption that on a long term average, the solarand internal gains will offset the heat loss when the mean daily outdoor temperature is 18.3 °C and thatthe energy consumption will be proportional to the difference between 18.3 °C and the mean daily tempera-ture. The degree-day method can estimate energy consumption very accurately if the building use and theefficiency of the HVAC equipment are sufficiently constant. However, for many applications, at least oneof the above parameters varies with time. For instance, the efficiency of a heat pump system and HVAC equip-ment may be affected directly or indirectly by outdoor temperature. In such cases, the bin method can yieldgood results for the annual energy consumption if different temperature intervals and time periods areevaluated separately. In the bin method, the energy consumption is calculated for several values of the outdoortemperature and multiplied by the number of hours in the temperature interval (bin) centered around thattemperature. Bin data is defined as the number of hours that the ambient temperature was in each of a setof equally sized intervals of ambient temperature.In the United States, the necessary bin weather data are available in the literature [2,3]. Some researchers[4–8] have developed bin weather data for other regions of the world. However, there is a lack of informationin the ASHRAE handbooks concerning the bin weather data required to perform energy calculations in build-ings in China. The practice of analysis of weather data for the design of HVAC systems and energy consump-tion predictions in China is quite new. For a long time, only the daily value of meteorological elements, such asdaily maximum, minimum and average temperature, was recorded and available in most meteorologicalobservations in China, but what was needed to obtain the bin weather data, such as temperature bin data,were the long term hourly values of air temperature. The study of bin weather data is very limited in China.Only a few attempts [9,10] in which bin weather data for several cities was given have been found in China.Obviously, this cannot meet the need for actual use and research. So, there is an urgent need for developing binweather data in China. The objective of this paper, therefore, is to study the hourly measured air temperaturedistribution and then to establish a model to generate bin weather data for the long term daily temperaturedata.2. Data usedZ. Jin et al. / Energy Conversion and Management 47 (2006) 1843–1850In this paper, to study the hourly ambient temperature variation and to establish and evaluate the model, aone year long hourly ambient temperature record for Nanjing in 2002 was used in the study. These data aretaken from the Climatological Center of Lukou Airport in Nanjing, which is located in the southeast of China(latitude 32.0°N, longitude 118.8°E, altitude 9 m).In addition, in order to create the bin weather data for Nanjing, typical weather year data was needed.Based on the long term meteorological data from 1961 to 1989 obtained from the China MeteorologicalAdministration, the typical weather year data for most cities in China has been studied in our former research[11] by means of the TMY (Typical Meteorological Year) method. The typical weather year for Nanjing isshown in Table 1. As only daily values of the meteorological elements were recorded and available in China,the data contained in the typical weather year data was also only daily values. In this study, the daily maxi-mum and minimum ambient temperature in the typical weather year data for Nanjing was used.3. Stochastic model to generate bin dataTraditionally, the generation of bin weather data needs long term hourly ambient temperature records.However, in the generation, the time information, namely the exact time that such a temperature occurredin a day, was omitted, and only the numerical value of the temperature was used. So, the value of each hourlyambient temperature can be treated as the independent random variable, and its distribution within the dailytemperature range can be analyzed by means of probability theory.3.1. Probability distribution of normalized hourly ambient temperatureSince the daily maximum and minimum temperatures and temperature range varied day by day, the con-cept of normalized hourly ambient temperature should be introduced to transform the hourly temperatures ineach day into a uniform scale. The new variable, normalized hourly ambient temperature is defined by^ ¼ttmintmaxtminwhere ^ may be termed the normalized hourly ambient temperature, tmaxand tminare the daily maximum andminimum temperatures, respectively, t is the hourly ambient temperature. Obviously, the normalized hourly ambient temperature ^ is a random variable that lies in the interval [0, 1].To analyze its distribution, the interval [0, 1] can be divided equally into several subintervals, and by means ofthe histogram method [12]iin each subinterval can be calculated by1137土木工程英文文献及翻译Based on the one year long hourly ambient temperature data in Nanjing, China, the probability density piwas calculated for the whole day and the 08:00–20:00 period, where the interval [0, 1] was equally divided into50 subintervals, namely n equals 50. The results are shown in Fig. 1.According to the discrete probability density data in Fig. 1, the probability density function of ^ can beobtained by a fitting method. In this study, the quadratic polynomialswere used to fit the probability density data, where a, b and c are coefficients. According to the property of theprobability density function, the following equation should be satisfiedAs shown in Fig. 1, the probability density curve obtained according to the probability density data pointsis also shown. The probability densit y functions that are fitted are described byp ¼ 2:7893^23:1228^ þ 1:6316 for the whole day periodp ¼ 2:2173^20:1827^ þ 0:3522 for the 08 : 00–20 : 00 period3.2. The generation of hourly ambient temperatureAs stated in the beginning of this paper, the objective of this study is to generate the hourly ambient tem-perature needed for bin weather data generation in the case that only the daily maximum and minimum tem-peratures are known. To do this, we can use the obtained probability density function to generate thenormalized hourly ambient temperature and then transform it to hourly temperature. This belongs to theproblem of how to simulate a random variable with a prescribed probability density function and can be doneon a computer by the method described in the literature [13]. For a given probability density function f ð^Þ, ifits distribution function F ð^Þ can be obtained and if u is a random variable with uniform distribution on [0, 1],thenF, we need only setAs stated above, the probability density function of the normalized ambient temperature was fitted using aone year long hourly temperature data. Based on the probability density function obtained, the random nor-malized hourly temperature can be generated. When the daily maximum and minimum temperature areknown, the normalized hourly temperature can be transformed to an actual temperature by the followingequationWhen the hourly temperature for a particular period of the day has been generated using the above method,the bin data can also be obtained. Because the normalized temperature generated using the model in this studyis a random variable, the bin data obtained from each generation shows somedifference, but it has much sim-ilarity. To obtain a stable result of bin data, the generation of the bin data can be performed enough times,and the bin data can be obtained by averaging the result of each generation. In this paper, 50 generations wereaveraged to generate the bin weather data.Z. Jin et al. / Energy Conversion and Management 47 (2006) 1843–18503.4. Methods of model evaluationThe performance of the model was evaluated in terms of the following statistical error test:土木工程英文文献及翻译一种产生bin气象数据的随机方法——中国南京周晋摘要:bin方法是一种众所周知且简捷的稳态的计算方法,可以用来预计建筑的冷热能耗。

土木工程行业英文文献综述

土木工程行业英文文献综述

土木工程行业英文文献综述The field of civil engineering has a rich history and plays a crucial role in the development of modern society. Civil engineering encompasses the design, construction, and maintenance of the built environment, including structures, transportation systems, and infrastructure. This literature review aims to provide an overview of the current state of research and developments in the civil engineering industry.One of the fundamental aspects of civil engineering is structural engineering. Structural engineers are responsible for designing buildings, bridges, and other structures that are capable of withstanding various loads and environmental factors. Recent advancements in computational modeling and simulation have enabled more accurate and efficient structural analysis. Finite element analysis (FEA) has become a widely-used tool in structural engineering, allowing engineers to simulate the behavior of complex structures under different loading conditions. Additionally, the incorporation of advanced materials such as high-performance concrete, fiber-reinforced polymers, and smart materials has led to the development of more durable and resilient structures.Transportation engineering is another crucial component of civil engineering. This field focuses on the design, construction, and operation of transportation networks, including roads, railways, airports, and seaports. With the increasing demand for efficient and sustainable transportation systems, researchers have explored various strategies to improve traffic flow, reduce congestion, and minimize environmental impact. Advancements in intelligent transportation systems (ITS), which utilize technologies such as sensors, communication networks, and data analytics, have enabled real-time monitoring and optimization of transportation networks.Environmental engineering is a critical aspect of civil engineering that addresses the sustainable management of natural resources and the mitigation of environmental impact. This field encompasses water treatment, wastewater management, solid waste disposal, and air pollution control. Researchers have explored innovative techniques for water purification, including membrane filtration, advanced oxidation processes, and biological treatment methods. Additionally, the integration of renewable energy sources, such as solar power and wind energy, into civil engineering projects has become increasingly prevalent.Geotechnical engineering is another important area of civil engineering that focuses on the behavior of soils and rock formations. Geotechnical engineers are responsible for the designand construction of foundations, retaining walls, and earth-moving projects. Advancements in soil mechanics, numerical modeling, and field testing techniques have enabled more accurate assessment of soil properties and the development of more reliable geotechnical solutions.In recent years, the civil engineering industry has also witnessed the emergence of innovative technologies and approaches, such as Building Information Modeling (BIM), which integrates digital representations of physical and functional characteristics of a project into a collaborative platform. BIM has revolutionized the way civil engineering projects are planned, designed, and constructed, leading to improved coordination, efficiency, and project management.Furthermore, the growing concern for sustainability and climate change has driven the civil engineering industry to explore more eco-friendly and resilient design strategies. Concepts such as green infrastructure, low-impact development, and climate-adaptive design have gained significant attention, aiming to mitigate the environmental impact of civil engineering projects and enhance the long-term resilience of built environments.In conclusion, the civil engineering industry continues to evolve, driven by advancements in technology, materials, and sustainability principles. Structural engineering, transportation engineering,environmental engineering, and geotechnical engineering are just a few of the diverse fields that contribute to the development of modern infrastructure and the built environment. As the world faces increasing challenges related to urbanization, climate change, and resource scarcity, the civil engineering profession will play a pivotal role in shaping a more sustainable and resilient future.。

土木工程英文参考文献

土木工程英文参考文献

Introduction to Civil Engineering PapersCivil Engineering for the development of a key role, first as a material foundation for the civil engineering construction materials, followed by the subsequent development of the design theory and construction technology. Every time a new quality of building materials, civil engineering will be a leap-style development.People can only rely on the early earth, wood and other natural materials in the construction activities, and later appeared in brick and tile that artificial materials, so that the first human to break the shackles of natural building materials. China in the eleventh century BC in the early Western Zhou Dynasty created the tile. The first brick in the fifth century BC to the third century BC, when the tomb of the Warring States Period. Brick and tile better than the mechanical properties of soil, materials, and easy to manufacture. The brick and tile so that people began to appear widely, to a large number of housing construction and urban flood control project, and so on. This civil engineering technology has been rapid development. Up to 18 to the 19th century, as long as two thousand years, brick and tile has been a major civil engineering construction materials, human civilization has made a great contribution to the even was also widely used in the present.The application of a large number of steel products is the second leap in civil engineering. Seventeen 1970s the use of pig iron, the early nineteenth century, the use of wrought iron bridges and the construction of housing, which is a prelude to the emergence of steel. From the beginning of the mid-nineteenth century, metallurgical industry, smelting and rolling out high tensile and compressive strength, ductility, uniformity of the quality of construction steel and then produce high-strength steel wire, steel cables. As a result of the need to adapt to the development of the steel structure have been flourishing. Inthe structure of network, cable structures to promote the gradual emergence of the structure of Yan in the form of flowers.From the brick building long-span structures, stone structures, a few meters of wood, steel structure to the development of tens of meters, a few hundred meters, until modern km above. So in the river, cross the bridge from shelves, on the ground since the construction of skyscrapers and high-rise tower, even in the laying of underground railway, to create an unprecedented miracle.In order to meet the needs of the development of steel works, on the basis of Newton's mechanics, material mechanics, structural mechanics, structural engineering design theory came into being, and so on. Construction machinery, construction technology and construction organization design theory also development, civil engineering from the experience of rising to become science, engineering practice and theoretical basis for both is a different place, which led to more rapid development of civil engineering. During the nineteenth century, 20, made of Portland cement, concrete has come out. Concrete can aggregate materials, easy-to-concrete structures forming, but the tensile strength of concrete is very small, limited use. By the middle of the nineteenth century, the surge in steel production, with the emergence of this new type of reinforced concrete composite construction materials, which bear the tension steel, concrete bear the pressure and play their own advantages. Since the beginning of the 20th century, reinforced concrete is widely used in various fields of civil engineering.From the beginning of the 1930s, there have been pre-stressed concrete. Pre-stressed concrete structure of the crack resistance, rigidity and carrying capacity, much higher than the reinforced concrete structure, which uses an even wider area. Civil Engineering into the reinforced concrete and prestressed concrete dominant historical period. Concreteengineering, civil engineering so that a new construction technology and engineering design of the structure of the theory. This is another leap in the development of civil engineering.A project to build the facilities in general to go through the investigation, design and construction in three stages, require the use of geological prospecting projects, hydro-geological survey, engineering survey, soil mechanics, mechanical engineering, engineering design, building materials, construction equipment, engineering machinery, building the economy , And other disciplines and construction technology, construction and other fields of knowledge, as well as computer and mechanical testing techniques. Civil engineering is therefore a broad range of integrated disciplines. With the progress in science and technology development and engineering practice, the civil engineering disciplines have also been developed into a broad connotation, the number of categories, the structure of complex integrated system.Civil Engineering is accompanied by the development of human society developed. It works in the construction of facilities reflect the various historical periods of socio-economic, cultural, scientific, technological development outlook, which civil society has become one of the historical development of the witness.In ancient times, people began to build simple houses, roads, bridges and still water channel to meet the simple life and production. Later, in order to adapt to the war, production and dissemination of religious life, as well as the needs of the construction of the city, canals, palaces, temples and other buildings.Many well-known works shown in this historical period of human creativity. For example, the Great Wall of China, Dujiangyan, the Grand Canal, Zhaozhou Bridge, Yingxian Wooden Tower, the pyramids of Egypt, Greece's Parthenon, Rome's water supply project,well-known churches, palaces and so on.After the industrial revolution, especially in the 20th century, on the one hand, civil society to put forward a new demand; On the other hand, all areas of society for the advancement of civil engineering to create good conditions. Thus this period of civil engineering has been advanced by leaps and bounds. All over the world there have been large-scale modernization of industrial plants, skyscrapers, nuclear power plants, highways and railways, long-span bridges, and large-diameter pipelines long tunnel, the Grand Canal, the big dams, airports, port and marine engineering, etc. . For civil engineering continually modern human society to create a new physical environment, human society, modern civilization has become an important part.Civil Engineering is a very practical subjects. In the early days, through the civil engineering practice, summing up successful experience, in particular, to draw lessons from the failure of developed. From the beginning of the 17th century, with Galileo and Newton as a pilot with the mechanics of the modern civil engineering practice, gradually formed the mechanical, structural mechanics, fluid mechanics, rock mechanics, civil engineering as the basis of theoretical subjects. This experience in civil engineering from the gradually developed into a science.In the course of the development of civil engineering, engineering practice often first experience in theory, engineering accidents often show a new unforeseen factors, triggering a new theory of the research and development. So far a number of projects dealing with the problem, is still very much rely on practical experience.Civil Engineering Technology with the main reason for the development of engineering practice and not by virtue of scientific experiments and theoretical studies, for two reasons: First, some of the objective situation is too complicated and difficult to faithfully carry outunderground engineering and deformation of the state and its changes over time, still need to refer to an analysis of engineering experience to judge. Second, only a new engineering practice in order to reveal new problems. For example, the construction of a high-rise buildings, high-rise tower and mast-span bridges, wind and earthquake engineering problems highlighted in order to develop this new theory and technology.In the long-term civil engineering practice, it is not only building great attention to the arts, has made outstanding achievements; and other works, but also through the choice of different materials, such as the use of stone, steel and reinforced concrete, with natural Environmental art in the construction of a number of very beautiful, very functional and good works. Ancient Great Wall of China, the modern world, many of the television tower and the bridge ramp Zhang, are cases in point.A building is closely bound up with people,for it provides with the necessary space to work and live in .As classified by their use ,buildings are mainly of two types :industrial buildings and civil buildings .industrial buildings are used by various factories or industrial production while civil buildings are those that are used by people for dwelling ,employment ,education and other social activities .Industrial buildings are factory buildings that are available for processing and manufacturing of various kinds ,in such fields as the mining industry ,the metallurgical industry ,machine building ,the chemical industry and the textile industry . factory buildings can be classified into two types single-story ones and multi-story ones .the construction of industrial buildings is the same as that of civil buildings .however ,industrial and civil buildings differ in the materials used and in the way they are used .Civil buildings are divided into two broad categories: residential buildings and publicthree necessary rooms : a living room ,a kitchen and a toilet .public buildings can be used in politics ,cultural activities ,administration work and other services ,such as schools, office buildings, parks ,hospitals ,shops ,stations ,theatres ,gymnasiums ,hotels ,exhibition halls ,bath pools ,and so on .all of them have different functions ,which in turn require different design types as well.Housing is the living quarters for human beings .the basic function of housing is to provide shelter from the elements ,but people today require much more that of their housing .a family moving into a new neighborhood will to know if the available housing meets its standards of safety ,health ,and comfort .a family will also ask how near the housing is to grain shops ,food markets ,schools ,stores ,the library ,a movie theater ,and the community center .In the mid-1960’s a most important value in housing was sufficient space both inside and out .a majority of families preferred single-family homes on about half an acre of land ,which would provide space for spare-time activities .in highly industrialized countries ,many families preferred to live as far out as possible from the center of a metropolitan area ,even if the wage earners had to travel some distance to their work .quite a large number of families preferred country housing to suburban housing because their chief aim was to get far away from noise ,crowding ,and confusion .the accessibility of public transportation had ceased to be a decisive factor in housing because most workers drove their cars to work .people we’re chiefly interested in the arrangement and size of rooms and the number of bedrooms .Before any of the building can begin ,plans have to be drawn to show what the building will be like ,the exact place in which it is to go and how everything is to be done.An important point in building design is the layout of rooms ,which should provide thedwelling house ,the layout may be considered under three categories : “day”, “night” ,and “services” .attention must be paid to the provision of easy communication between these areas .the “day “rooms generally include a dining-room ,sitting-room and kitchen ,but other rooms ,such as a study ,may be added ,and there may be a hall .the living-room ,which is generally the largest ,often serves as a dining-room ,too ,or the kitchen may have a dining alcove .the “night “rooms consist of the bedrooms .the “services “comprise the kitchen ,bathrooms ,larder ,and water-closets .the kitchen and larder connect the services with the day rooms .It is also essential to consider the question of outlook from the various rooms ,and those most in use should preferably face south as possible .it is ,however ,often very difficult to meet the optimum requirements ,both on account of the surroundings and the location of the roads .in resolving these complex problems ,it is also necessary to follow the local town-planning regulations which are concerned with public amenities ,density of population ,height of buildings ,proportion of green space to dwellings ,building lines ,the general appearance of new properties in relation to the neighbourhood ,and so on . There is little standardization in industrial buildings although such buildings still need to comply with local town-planning regulations .the modern trend is towards light ,airy factory buildings .generally of reinforced concrete or metal construction ,a factory can be given a “shed ”type ridge roof ,incorporating windows facing north so as to give evenly distributed natural lighting without sun-glare .。

土木工程外文参考文献

土木工程外文参考文献

ÃCorresponding author.Tel.:+86-411-8470-8512x8208;fax:+86-411-8470-8501.E-mail address:hnli@(H.-N.Li).0141-0296/$-see front matter#2004Elsevier Ltd.All rights reserved. doi:10.1016/j.engstruct.2004.05.018not only the structural status,for instance stress, displacement,acceleration etc.,but also influential environmental parameters,such as wind speed,tem-perature and the quality ofits f oundation.Since a large number ofsensors will be involved in a health monitor-ing system,the acquisition,transmission and storage of a large quantity ofdata f or such continuous monitor-ing is a challenging task.For instance,raw data are acquired at a rate of63.46MB per hour f or the TsingMa and Kap Shui Mun Bridges and55.87MB per hour for TingKau Bridge[3].Therefore,many wireless[4,5],GPS[6]or GIS[7]based data acqui-sition,transmission methods and data archival and management architectures[8]were proposed to deal with this problem.Though it is very important to embed sensors and collect data successfully for a health monitoring application,thefinal step is to interpret correctly the data from various types of sensors to reach critical decisions regarding the load capacity,sys-tem reliability,i.e.the health status ofthe structure[9]. At this crucial step,prognostic and diagnostic algo-rithms based on modal analysis,pattern recognition and time series analysis are among the most effective methods to detect the presence,location,magnitude, and extent ofstructural f aults[10].Moreover,the information analyzed should be user friendly to improve operation and maintenance management deci-sions.Another crucial function of SHM is the ability to alert ongoing dangers or future accidents in advance. Though it is not a simple task to realize fully such an appealing scenario,several projects had been under-taken to implement partially SHM systems from research laboratories tofield applications.TsingMa, Kap Shui Mun,and TingKau bridges,connecting Hong Kong and its new airport,are the most note-worthy bridges being heavily instrumented for health monitoring.Wind load is a major concern ofthese bridges as well as temperature,traffic load,geometric configuration,strain,and global dynamic character-istics.Among the786permanently installed sensors in TsingMa Bridge,anemometers,temperature,strain and accelerometer sensors comprise a major portion.Moni-toring results are satisfactory and have verified design performance[11].Similar sensors were also used in the health monitoring system ofthe Akashi Kaikyo Bridge in Japan.The transversal displacement of5.17m monitored in September1998agreed well with numeri-cal modore Barry Bridge and Benicia-Martinez bridge ofthe US are equally important examples ofSHM[12].In Commodore Barry Bridge, real-time images and data from nearly500channels combined with itsfinite element model are used for maintenance and management ofthe bridge to the maximum benefit.Other significant efforts in imple-menting health monitoring systems include bridges in Korea,Canada,India and Colombia[13].Most ofthe conventional sensors used in the above mentioned health monitoring applications are based on transmission ofelectric signals.Their limitations are becoming more and more manifest.These sensors are usually not small or durable enough to be embedded in a structure to measure interior properties.They are local(or point)sensors,which are restricted to measure only parameters at one location and cannot be easily multiplexed.The long lead lines also pose problems for large civil structures,which often span several or tens ofkilometers.In some cases,the signals could not be discriminated from noise because of electrical or mag-netic interference(EMI).In addition,various demodu-lation techniques are required for different sensors. They all add in increasing the inconveniences ofcon-ventional sensors in SHM.Fiber optic sensors(FOSs) are promising sensing alternatives in civil SHM systems and future smart structures.They exhibit several advantages such as,flexibility,embeddability,multi-plexity and EMI immunity[14],as compared with traditional sensors.The past20years have witnessed an intense international research in thefield ofoptical fiber sensing.In the following sections,we will describe this enabling technology and review its health monitor-ing applications to civil engineering.2.Threefiber optic sensors for structural health monitoringThefirstfiber optic sensor,a closed-loopfiber gyro, was invented to replace mechanical spinning gyros on the Delta Rocket in1978[15].Conception ofsuch FOSs originated fromfiber optic communications. Opticalfiber experiences geometrical(size and shape) and optical(refractive index and mode conversion) changes due to various environmental perturbations while conveying light from one place to another.These phenomena perplexed efforts to minimize such adverse influences so that signal transmission is smooth and reliable.However,it is found that such optical changes can be employed to measure the external environment parameters.Opticfiber thus found its niche in sensor applications.Investigations showed that the sensitive perturbations in temperature,strain,rotation,electric and magnetic currents,etc.,can be converted or enco-ded into corresponding changes,such as amplitude (intensity),phase,frequency,wavelength and polariza-tion in the optical properties ofthe transmitted light. These changes can be eventually detected by appropri-ate demodulation systems[16,17].With rapid advances in communication and start ofmass production offiber optic cables,fiber optic sensing is growing to be a pros-perous industry,benefiting from the decreasingfiber prices.Many techniques have been devised to provide solutions to measure a broad range ofphysical and1648H.-N.Li et al./Engineering Structures26(2004)1647–1657chemical parameters.As a consequence,fiber optic based measurement systems have made the transition from research laboratories to practical engineering applications,and have found wide applications in aero-space,composites,medicine,chemical products,con-crete structures,and in the electrical power industry. The market volume ofFOSs is hypothesized to rise from US$305millions in1997to this year’s US$550 millions[18],among which temperature,strain and pressure sensors account for about40%of the total FOS products[19].Extensive efforts are now engaged to realize economic FOSs and associated interrogation systems and to explore wider engineering applications. Opticalfibers,which usually consist ofthree layers:fiber core,cladding and jacket,are dielectric devices used to confine and guide light.The majority ofoptical fibers used in sensing applications have silica glass cores and claddings,and the refractive index of the cladding is lower than that ofthe core to satisf y the condition ofSnell’s law f or total internal reflection and thus confine the propagation ofthe light along thefiber core only.The outer layer ofa FOS,called jacket,is usually made ofplastic to provide thefiber with appro-priate mechanical strength and protect it from damage or moisture absorption.In some sensing applications,a specialized jacket is required to enhance thefiber’s measurement sensitivity and to accommodate the host structure.In general,an FOS is characterized by its high sensi-tivity when compared to other types ofsensors.It is also passive in nature due to its dielectric construction. Specially preparedfibers can withstand high tempera-ture and other harsh environments.In telemetry and remote sensing applications,it is possible to use a seg-ment ofthefiber as a sensor gauge and a long length ofthe same or anotherfiber to convey the sensed inf or-mation to a remote station.Deployment ofdistributed and array sensors covering extensive structures and geographical locations is also feasible.With many sig-nal processing devices(splitter,combiner,multiplexer,filter,delay line,etc.)being made offiber elements,an all-fiber measuring system can be realized.Table1lists the FOSs available to civil engineering applications and their categories.One method of classifying FOSs is based on its light characteristics (intensity,wavelength,phase,or polarization)that is affected by the parameter to be sensed.Another method classifies an FOS by whether the light in the sensing segment is modified inside or outside thefiber (intrinsic or extrinsic).FOSs can also be classified as local(or point),quasi-distributed and distributed sen-sors depending on the sensing range.This method of classification is adopted here to organize the rest ofthis section.2.1.Localfiber optic sensorsMany intensity based sensors,such as microbend sensors,and most ofthe interf erometric FOSs are local sensors,which can measure changes at specified local points in a structure.Interferometric FOSs are by far the most commonly used local sensors since they offer the best sensitivity.This sensing technique is based primarily on detecting the optical phase change induced in the light as it propagates along the optical fiber.Light from a source is equally divided into two fiber-guided paths(one is a reference path).The beams are then recombined to mix coherently and form a ‘‘fringe pattern’’which is directly related to the optical phase difference experienced between the two optical beams.The most common configurations ofsuch inter-ferometric sensors are the Mach-Zehnder,Michelson and Fabry–Perot FOSs[20,21].Among them,the Fabry–Perot(F-P cavity)FOS and the so-called long gage FOS(LG FOSs)are the two types oflocal sensors commonly utilized in civil engineering.Fabry–PerotTable1Fiber optic sensors for civil structural health monitoringSensors Mesurands Linearresponse Resolution Range ModulationmethodIntrinsic/extrinsicLocal Fabry–Perot Strain a Y0.01%gage length c10,000le Phase Both Long gage sensor Displacement Y0.2%gage length d50m Phase Intrinsic Quasi-distributedFibre Bragg grating Strain b Y1l strain5000le Wavelength IntrinsicDistributed Raman/Rayleigh(OTDR)Temperature/strain N0.5m/1v C2000m e Intensity IntrinsicBrillouin(BOTDR)Temperature/strain N0.5m/1v C2000m Intensity Intrinsica Can be configured to measure displacement,pressure,temperature.b Can be configured to measure displacement,acceleration,pressure,relativefissure and inclination,etc.c Resolution as high as0.1l strain.d Resolution as high as0.2l strain.e Up to25km with spatial resolution of5m.H.-N.Li et al./Engineering Structures26(2004)1647–16571649FOSs,which can provide absolute Fabry–Perot cavity length measurements with superior accuracy(Fig.1), are based on white-light cross-correlation principle.In addition to its strain-sensing ability,an F-P sensor can also measure pressure,displacement and temperature with different configurations.LGFOSs are based on two low-coherent double Michelson interferometers (Fig.2).Both sensors measure the average strain between twofixed points along the gage with optional temperature compensation.The length ofthe long gage sensors ranges from0.2to50m.2.2.Quasi-distributed sensorsFiber Bragg grating(FBG)sensor,which can be easily multiplexed to measure strains at many loca-tions,is a kind oftypical quasi-distributed sensor.A Bragg grating is a permanent periodic modulation of the refractive index in the core of a single mode optical fiber.The change ofthe core ref raction index is between10À5and10À3,and the length ofa Bragg grat-ing is usually around10mm,which is much shorter than that ofa long period grating(LPG)[22].This technology originated from the discovery of photo-sensitivity ofgermanium doped silica by Hill et al.[23] ter Meltz et al.[24]devised a more efficient transverse holographic method,which enormously increased the scope ofFBG s’applications.Now the phase mask technique supersedes the above two meth-ods and is commonly used to form commercially the in-core gratings[25].Techniques such as hydrogen loading andflame brushing can be adopted to enhance the germanium doped single mode opticalfiber’s pho-tosensitivity prior to laser irradiation[26].The principle ofan FBG is described as f ollows: When light within afiber impinges upon Bragg grat-ings,constructive interference between the forward wave and the contra-propagating light wave leads to narrowband back-reflection oflight when the Bragg(or phase match)condition is satisfied(Fig.3).Because of this,afiber Bragg gating can serve as an intrinsic sensor.Any local strain or temperature changes alter the index of core refraction and the grating period,fol-lowed by changes in wavelength ofthe reflected light. Wavelength changes can be detected by an interrog-ator,which employs edgefilters,tunable narrowband filters,or CCD spectrometers[27,28].Tunable narrow-bandfilters are commercially popular interrogation sys-tems.Fig.3shows the wavelength multiplexing schemes,principles and wavelength shifts of FBG sen-sors.There are several major concerns in selecting FBGs and the associated interrogation systems.For instance,spectral overlap ofthe gratings changes adjac-ent desirable wavelength[29].For another instance, sidebands in the measured wavelength,the interrog-ationfilter and the tunable light source also introduce errors in the system.Despite these concerns,FBG sensors have a unique property over other FOSs in that they encode the wavelength,which is an absolute parameter and does not suffer from disturbances of the light paths.FBG sensors could be particularly useful when gratings with different periods are arranged along an opticalfiber. Each ofthe reflected signals will have a unique wave-length and can be easily monitored,thus achieving multiplexing ofthe outputs ofmultiple sensors using a singlefiber(Fig.3).Currently,up to64FBGs can be theoretically wavelength-multiplexed in onefiber,per-mitting quasi-distributive measurement ofstrain.FBG sensors are preferred in many civil engineering applica-tions and have been successfully employed in several full-scale structures requiring multiple-point sensing distributed over a long range.2.3.Distributedfiber optic sensorsDistributed sensors are most suitable for large struc-tural applications,since all the segments ofan optical fiber act as sensors,and therefore,the perturbations within various segments ofthe structure can be sensed. Distributed sensors are based on the modulation of light intensity in thefiber.Fracture losses or local damages in a structure cause light intensity variations. Two major distributed sensor methodologies are the optical time domain reflectometry(OTDR)and the Brillouin scattering.In the OTDR,Rayleigh and Fresnel scatterings are used for sensingstructuralperturbations.On the other hand,Brillouin scattering detects the Doppler shift in light frequency which is related to the measurements.Distributed sensors have not found widespread usage in civil structural applica-tions.The main reasons are their insufficient resolu-tions,weak detectable signals,and cumbersome demodulation systems.However,they have a great potential in civil engineering due to their inherent distributive nature.3.Recent progress of FOS health monitoring in civil engineeringFOSs offer great potential for SHM applications.Their significance to health monitoring applications stems from the following facts:(1)Long life cycle.They are made from a very durable material (i.e.silica)that is corrosion resistant and withstands high tensile loading (up to 5%elongation,i.e.50,000le );(2)High temperature endurance.They can measure temperaturefrom À200to 800v C with a silica core and 1500vC with a sapphire core.The measuring resolution can bebetter than 0.1vC;(3)Flexibility.They can be applied to complex surfaces and difficult-to-reach areas(i.e.around the circumference of a round object,along sharp corners or across welds),capable ofboth local and distributive measurements (ranging from 1mm to tens ofkilometers);(4)Immunity to EMI.They can operate in electrically noisy environments and can transfer sensing data over a long distance without EMI contamination;(5)Electrical isolation.They are non-conductive and suitable for embedment with minimum impact to the host structure;(6)Quasi-distributed or distributed sensing capacity.They can perform in-situ sensing at multiple locations required by health moni-toring oflarge civil structures and can be easily multi-plexed by time or wavelength methods;(7)Economy.They are already cost-competitive against conventional sensors and their prices will still decrease with the rapid development offiber optic communication industry and wide exploration ofFOSs.Integration of FOSs with civil infrastructure for SHM is an active research field.While the benefits of long term structural monitoring are yet to be fully realized,several applications have been demonstrated to date.In these applications,optical time domain reflectometry,Bragg gratings,Fabry–Perot and the LGFOSs have effectively complemented orevenFig.3.Multiplexing schemes,principles and wavelength shift of fiber Bragg grating sensors.H.-N.Li et al./Engineering Structures 26(2004)1647–16571651replaced some sensors.The rest ofthis section will review these demonstrations.3.1.BuildingsFOSs have been successfully applied to buildings for strain and temperature measurement.Early in2001, four long gage Bragg grating sensors were installed across,above and under the primary arch ofthe Cathedral ofComo in Northern Italy to identif y any significant structural deterioration to protect this sig-nificant cultural heritage built in1396[30].These four sensors were installed using surface mounting brackets. The sensor installed across the arch had a total gauge length of7m with a spring mechanism and the rest all have a gauge length of100mm.Each sensor has two serially connected Bragg gratings.One grating measures strain,while the other monitors temperature. Displacement resolution of0.1l m and temperature resolution of0.1v C were achieved with the technique offiber Fabry–Perot tunablefilter demodulation sys-tem.The eight-month period measurement showed that the temperature was consistent with seasonal variation and the displacements were not substantial.Along with the high resolution ofFOSs,the advantage ofembedd-ability is often exploited in health monitoring. Recently,in Japan,64FBG sensors were embedded in a12-floor steel frame building with the damage toler-ance construction technique,which employs dampers to absorb seismic energy[31].These embedded sensors can measure relative displacements,strains,and tem-peratures.They were multiplexed in six single optical fibers to monitor the performance of these dampers.In addition to the applications oflocal and quasi-distributed monitoring systems,well distributedfiber optic sensing also became a reality.In Korea,a single mode opticalfiber of1400m was bonded on the surfaces of a4-storey building to monitor temperature distribution.The optical signals were demodulated by the stimulated Brillouin optical time domain reflec-tometry(BOTDR).Continuous monitoring results showed that the temperature distribution at night generallyfluctuated less than that at noon and the temperature normally changed up to4v C in one day[32]. One challenge in the application ofFOS in building monitoring is to measure the tip displacement oftall buildings.This parameter is necessary to evaluate the safety of a building,but difficult or expensive to measure by traditional sensors.3.2.PilesPiles are very important to support structures and protect buildings from shocks or earthquakes.In December2001,30FBG sensors were multiplexed into six opticalfiber arrays for driving test monitoring of two composite marine piles[33].Among them,four arrays consisting ofsix FBG s along the pile were used to monitor the strains and two arrays consisted of three FBGs were used to monitor the temperatures. The FBG sensors were interrogated by an unit using fiber Fabry–Perot tunablefilter technology.The piles tested are60-ft long with a diameter of two ft.A three-point bending test was performed to ensure the survi-vability ofal the FBG s and the insensitivity ofthe FBG temperature sensors to mechanical strain.Then, driving tests were conducted and real-time monitoring showed that apparent bending existed in the pile. Although the survivability ofFBG s in pile driving was verified,thefiber lead ofa strain-sensing array was broken and the readings ofthe FBG temperature sen-sor suffered from strain cross-sensitivity.Similar pile drivings were conducted to test the foun-dation ofa new f actory,which requires a highly stable base,in the Tainan Scientific Park,Taiwan[34].All the six tested piles had the same dimension with a diameter of1.2m and a length of35m.Nine4-m LG FOSs were utilized in the compression and pullout tests ofa pile to measure the strain and load eccentricity.Sixteen4-m LGFOSs were installed in parallel on the opposite side ofa pile to monitor the average curvature,which were used later to compute the horizontal displacement by double integration.From the above tests,Young’s modulus,longitudinal strain,vertical displacement and force in the piles were measured.In addition,proper-ties ofsoil,critical strain when crack occurs in the pile, ultimate load capacity ofa pile,and f ailure mode in the interface of soil and pile were also measured.The sensors and demodulation system were provided by Smartec SA.3.3.BridgesBridges,especially concrete bridges,are the most monitored civil structures by FOSs.Intelligent Sensing for Innovative Structures(ISIS,Canada)has equipped up to six bridges withfiber optic sensing systems that allow remote monitoring since1993[35].In its first instrumented bridge,Beddington Trail Bridge (Alberta),18out ofthe20FBG sensors,which were originally installed,are still functioning afterfive years ofoperation.Atfirst,these FBG sensors,demodulated by a grating-fiber/laser system in conjunction with a Burleigh Jr.wavemeter with a resolution ofonly about Æ40le,were used to monitor the stress relaxation in the steel and the carbonfiber reinforced polymer (CFRP)tendons.Then by a more advancedfiber optic grating indicator(FLS3500RTM),a strain resolution of1le was achieved and dynamic responses ofa low speed truck could be measured to estimate roughly the weight ofthe truck and its driving direction[36]. Among the six bridges,the Taylor Bridge(Manitoba)1652H.-N.Li et al./Engineering Structures26(2004)1647–1657was fully instrumented.The CFRP girders of the Taylor Bridge were attached to63FBG sensors and two multi-Bragg sensors,which were close to the26 conventional strain gages for comparison.The FBG sensors at the mid-span,demodulated by a32-channel fiber optic grating indicator(FLS3500R),were to measure the maximum strain,while the sensors at the girder ends were designed to monitor the transfer length ofpre-stressing tendons.Sixty percent ofthe properly sealed strain gages malfunctioned due to excessive moisture resulting from steam curing process, while the FOSs were not affected and all survived.This demonstrates again the FOSs’compatibility with concrete and its potential as preferred sensors in SHM. In Taylor Bridge’s remote monitoring system,the online strain or temperature data can be accessed in the engineer’s office by logging onto the acquisition computer at the bridge site through a modem and a phone line[37].Therefore,the conditions of the bridge can be continuously monitored in a remote office using a desktop computer.The other four bridges integrated with FOSs are the Crowchild Trail Bridge(Alberta), the Salmon River Bridge(Nova Scotia),the Joffre Bridge(Quebec)and the Confederation Bridge(Prince Edward Island/New Brunswick).In these bridges,all the installed FOSs performed well.In Switzerland,the Siggenthal Bridge with an arch span of117m was built over the Limmart River in Baden in2000.Fifty-eight LGFOSs,whose gage length ranges from3to5m,were embedded in pairs near the top and bottom surfaces of the concrete arch slab dur-ing construction.Each pair consisted oftwo identical sensors and were installed parallel to the arch length to monitor the deformations of arch segments.From the measured deformation of each arch segment,concrete deformations,the curvatures in the vertical plane and perpendicular displacements ofthe whole concrete arch during both the construction and in-service period were determined.A portable reading unit(SOFO)was inter-mittently set near the arch feet of the bridge to check the LGFOSs.Preliminary monitoring results showed that the daily temperaturefluctuation during summer had particularly large influence on the arch and should be taken into consideration during the bridge design phase[38].Also in Switzerland,the Versoix Bridge was equipped with104such LGFOSs to monitor long term deformations of the bridge.The Viaduc des Vaux Bridge is another bridge that has been monitored by FOSs[39].A total of12FBG sensors were attached to the interior walls ofa section ofa box-girder at the push and pull stage during the construction period,and the primary goal was to mea-sure the resulting strain on the box-girder web due to transverse loads induced by the pier during the launch. The data obtained not only indicated that design toler-ances were not exceeded but also provided useful records ofunique diagnostic events such as the curva-ture defects present in the sliding shoe device. Although FOSs have been embedded or attached to many concrete bridges,steel structures equipped with FOSs are not so common.This may be is attributed to the fact that it is almost impossible to embed an FOS in a steel structure element.Surface-bonding,at present,is the only way to integrate an FOS with a steel structure, and the benefits ofutilizing FOSs in such situations are not evident.The Waterbury Bridge in Vermont,the US, is such an example[40].This bridge is a67m steel truss bridge spanning the Winooski River.Thirty-six chloride FOSs were embedded at various points along the bridge to monitor the chloride penetration into the deck.The chloride sensor is based on the interaction between the chloride ions and a sol–gelfilm,which is positioned between the input–outputfiber.Thefilm’s transmission characteristics changes in terms ofcolor(f rom milky white to pink);thus overallfiber’s transmission change and chloride ion’s concentration are determined. Another16FBG strain sensors were placed at points of the reinforcement bars with maximum strains to moni-tor the strain variations.Their efforts showed that instrumentation ofFOSs may cost up to10%higher in certain cases.3.4.Highway traffic monitoringAlthough FOSs embedded in the Beddington Trail Bridge is intended for long term SHM and therefore employ low rate data sampling system,they can still weigh vehicles running slowly.However,these FOSs are inadequate for traffic monitoring,such as classify-ing vehicles,on a regular highway without traffic inter-ruption since the FOSs used for such purposes demand a high-sampling-rate data acquisition system in addition to high measuring sensitivity[41].A traffic sensor is basically a sensor embedded on the surface of a road to detect trafficflow.The dynamic testing system developed by Udd et al.can achieve less than0.1micro-strain resolution with a dynamic range of400micro-strain at10kHz sampling rate,which can satisfy such traffic monitoring requirements.They installed28specially designed FBG traffic sensors(26 survived)in surface-cut slots of the Horsetail Falls Bridge in the Colombia River Gorge National Scenic Area ofthe United States[42],and tested the monitor-ing system by running vehicles ofdifferent weights at a speed of10–18km per hour.Then,five long gage FBG sensors were installed in the I-84freeway to test the ability ofthese sensors as vehicle classifier and counter [43].Over halfa year’s monitoring showed that the sensing systems are sufficient to discriminate tractor–trailer and buses,and even the traffic in adjacent lanes in some cases.The amplitude ofthe signal appears to be closely proportional to the vehicle weight,the speedH.-N.Li et al./Engineering Structures26(2004)1647–16571653。

土木工程英语文献原文

土木工程英语文献原文

Civil engineering introduction papersAbstract: the civil engineering is a huge discipline, but the main one is building, building whether in China or abroad, has a long history, long-term development process. The world is changing every day, but the building also along with the progress of science and development. Mechanics findings, material of update, ever more scientific technology into the building.But before a room with a tile to cover the top of the house, now for comfort, different ideas, different scientific, promoted the development of civil engineering, making it more perfect.[key words] : civil engineering; Architecture; Mechanics, Materials.Civil engineering is build various projects collectively. It was meant to be and "military project" corresponding. In English the history of Civil Engineering, mechanical Engineering, electrical Engineering, chemical Engineering belong to to Engineering, because they all have MinYongXing. Later, as the project development of science and technology, mechanical, electrical, chemical has gradually formed independent scientific, to Engineering became Civil Engineering of specialized nouns. So far, in English, to Engineering include water conservancy project, port Engineering, While in our country, water conservancy projects and port projects also become very close and civil engineering relatively independent branch. Civil engineering construction of object, both refers to that built on the ground, underground water engineering facilities, also refers to applied materials equipment and conduct of the investigation, design and construction, maintenance, repair and other professional technology.Civil engineering is a kind of with people's food, clothing, shelter and transportation has close relation of the project. Among them with "live" relationship is directly. Because, to solve the "live" problem must build various types of buildings. To solve the "line, food and clothes" problem both direct side, but also a indirect side. "Line", must build railways, roads, Bridges, "Feed", must be well drilling water, water conservancy, farm irrigation, drainage water supply for the city, that is direct relation. Indirectly relationship is no matter what you do, manufacturing cars, ships, or spinning and weaving, clothing, or even production steel, launch satellites, conducting scientific research activities are inseparable from build various buildings, structures and build all kinds of project facilities.Civil engineering with the progress of human society and development, yet has evolved into large-scale comprehensive discipline, it has out many branch, such as: architectural engineering, the railway engineering, road engineering, bridge engineering, special engineering structure, waterand wastewater engineering, port engineering, hydraulic engineering, environment engineering disciplines. [1]Civil engineering as an important basic disciplines, and has its important attributes of: integrated, sociality, practicality, unity. Civil engineering for the development of national economy and the improvement of people's life provides an important material and technical basis, for many industrial invigoration played a role in promoting, engineering construction is the formation of a fixed asset basic production process, therefore, construction and real estate become in many countries and regions, economic powerhouses.Construction project is housing planning, survey, design, construction of the floorboard. Purpose is for human life and production provide places.Houses will be like a man, it's like a man's life planning environment is responsible by the planners, Its layout and artistic processing, corresponding to the body shape looks and temperament, is responsible by the architect, Its structure is like a person's bones and life expectancy, the structural engineer is responsible, Its water, heating ventilation and electrical facilities such as the human organ and the nerve, is by the equipment engineer is responsible for. Also like nature intact shaped like people, in the city I district planning based on build houses, and is the construction unit, reconnaissance unit, design unit of various design engineers and construction units comprehensive coordination and cooperation process.After all, but is structural stress body reaction force and the internal stress and how external force balance. Building to tackle, also must solve the problem is mechanical problems. We have to solve the problem of discipline called architectural mechanics. Architectural mechanics have can be divided into: statics, material mechanics and structural mechanics three mechanical system. Architectural mechanics is discussion and research building structure and component in load and other factors affecting the working condition of, also is the building of intensity, stiffness and stability. In load, bear load and load of structure and component can cause the surrounding objects in their function, and the object itself by the load effect and deformation, and there is the possibility of damage, but the structure itself has certain resistance to deformation and destruction of competence, and the bearing capacity of the structure size is and component of materials, cross section, and the structural properties of geometry size, working conditions and structure circumstance relevant. While these relationships can be improved by mechanics formula solved through calculation.Building materials in building and has a pivotal role. Building material is with human society productivity and science and technologyimproves gradually developed. In ancient times, the human lives, the line USES is the rocks andTrees. The 4th century BC, 12 ~ has created a tile and brick, humans are only useful synthetic materials made of housing. The 17th century had cast iron and ShouTie later, until the eighteenth century had Portland cement, just make later reinforced concrete engineering get vigorous development. Now all sorts of high-strength structural materials, new decoration materials and waterproof material development, criterion and 20th century since mid organic polymer materials in civil engineering are closely related to the widely application. In all materials, the most main and most popular is steel, concrete, lumber, masonry. In recent years, by using two kinds of material advantage, will make them together, the combination of structure was developed. Now, architecture, engineering quality fit and unfit quality usually adopted materials quality, performance and using reasonable or not have direct connection, in meet the same technical indicators and quality requirements, under the precondition of choice of different material is different, use method of engineering cost has direct impact.In construction process, building construction is and architectural mechanics, building materials also important links. Construction is to the mind of the designer, intention and idea into realistic process, from the ancient holeJuChao place to now skyscrapers, from rural to urban country road elevated road all need through "construction" means. A construction project, including many jobs such as dredging engineering, deep foundation pit bracing engineering, foundation engineering, reinforced concrete structure engineering, structural lifting project, waterproofing, decorate projects, each type of project has its own rules, all need according to different construction object and construction environment conditions using relevant construction technology, in work-site.whenever while, need and the relevant hydropower and other equipment composition of a whole, each project between reasonable organizing and coordination, better play investment benefit. Civil engineering construction in the benefit, while also issued by the state in strict accordance with the relevant construction technology standard, thus further enhance China's construction level to ensure construction quality, reduce the cost for the project.Reference:[1] LuoFuWu editor. Civil engineering (professional). Introduction to wuhan. Wuhan university of technology press. 2007[2] WangFuChuan, palace rice expensive editor. Construction engineering materials. Beijing. Science and technology literature press. 2002[3] jiang see whales, zhiming editor. Civil engineering introduction of higher education press. Beijing.. 1992。

土木工程中结构设计与施工技术相关英文参考文献

土木工程中结构设计与施工技术相关英文参考文献

土木工程中结构设计与施工技术相关英文参考文献全文共四篇示例,供读者参考第一篇示例:3. "Construction Planning, Equipment, and Methods" by Robert L. Peurifoy, Clifford J. Schexnayder, and Aviad ShapiraConstruction is a complex and dynamic process that requires careful planning and coordination of resources. This book provides a comprehensive overview of construction planning, equipment, and methods, and covers topics such as project management, scheduling, and cost estimation.第二篇示例:Title: Literature Review on Structural Design and Construction Technology in Civil EngineeringIntroductionCivil engineering is a broad field that encompasses various aspects of infrastructure development, including the design and construction of buildings, bridges, roads, and other structures. One key aspect of civil engineering is structural design, which involves the analysis and planning of a structure to ensure itssafety, durability, and functionality. In addition to design, the construction technology used to build the structure also plays a crucial role in its overall performance and longevity. In this literature review, we will explore some key references related to structural design and construction technology in civil engineering.Structural Design References第三篇示例:IntroductionStructural design and construction technology are essential components of civil engineering, providing the framework for building safe and durable structures. This article will explore several key references related to structural design and construction technology in civil engineering.第四篇示例:土木工程中结构设计与施工技术是土木工程领域中非常重要的一个方面。

土木概论的参考文献

土木概论的参考文献

土木概论的参考文献土木工程是工程学中的一个重要分支,研究的是土地和建筑物的设计、建设和维护。

本文将介绍一些关于土木工程方面的重要参考文献,以帮助读者深入了解这个领域。

1. "Principles of Foundation Engineering" by Braja M. Das这本经典教材是基础工程学中的权威教材之一。

它详细介绍了土壤力学和地基设计的原理和方法。

作者通过丰富的图表和实际案例,向读者提供了解决复杂基础工程问题的工具和知识。

2. "Structural Analysis" by R.C. Hibbeler这本教材是结构工程学的经典之作,涵盖了结构分析的各个方面。

它以清晰简明的语言介绍了不同类型结构的分析方法,包括梁、柱、框架和悬挂结构。

该书还包含了大量的实例和练习题,帮助读者巩固理论知识并应用于实践中。

3. "Construction Methods and Management" by S.W. Nunnally这本教材详细介绍了建筑施工的方法和管理。

作者通过系统性的讲解,向读者展示了不同类型建筑项目的施工流程和管理技术。

该书还包括实例和案例研究,帮助读者了解施工行业的最新趋势和挑战。

4. "Geotechnical Engineering: Principles and Practices" by Donald P. Coduto这本教材是土力学领域的经典之作。

它涵盖了岩土工程的各个方面,包括土体力学、土壤力学和地基设计。

作者通过理论和实践结合的方式,向读者介绍了解决复杂地质工程问题的方法和策略。

5. "Transportation Engineering: An Introduction" by C.JotinKhisty and B.Kent Lall这本教材全面介绍了交通工程学的基本原理和应用。

土木工程毕业设计英文文献

土木工程毕业设计英文文献

1. Introduction
The Georgia Department of TransportationG(GDOT) has wellmaintained and timely rehabbed pavements and has enjoyed the reputation as having the best pavements among the fifty states in USA. One of the reasons that GDOT can achieve such high performance standards for its pavements is the utilization of a Pavement Condition Evaluation SystemG (PACES, 1996) to evaluate the pavement conditions annually for the entire highway system in Georgia for the past 15 years. Results of the annual PACES evaluations are then used to develop pavement maintenance and rehabilitation prioritization schedules. The PACES was designed to indicate the extent and types of surface distresses on a flexible pavement at the time of the pavement condition survey. Futhermore, the other advantage of PACES system was that it could link with other vital road characteristic data to make it possible to build the pavement performance database. In the past, the annual maintenance and rehabilitation prioritization scheduling was develop an intelligent prioritization schedule became ever more important for the sake of efficiency and as many of the experienced engineers are retired from GDOT. If the pavement performance prediction model can be developed based on the past PACES data, the remaining service lives for pavements can be forecasted. This would be very useful for schedule for scheduling the rehabilitation and determining the funding level required to

土木工程中结构设计与施工技术相关英文参考文献

土木工程中结构设计与施工技术相关英文参考文献

土木工程中结构设计与施工技术相关英文参考文献在土木工程中,结构设计与施工技术的相关英文参考文献有很多,以下是一些可供参考的文献:1.建筑设计中的结构设计与施工技术的英文参考文献"Structural Design in Architecture: Principles and Practice" by John S. Chen and Cheng K. Chau."Architectural Design: Form, Function, and Expression" by George A. Lane."Structural Design for Architects" by John S. Chen.2.土木工程中结构设计与施工技术的英文参考文献"Structural Design in Civil Engineering: Principles and Practice" by John A. Mathews."Civil Engineering Structures: Design, Analysis, and Construction" by R. Burridge and R. Kerry."Structural Analysis in Civil Engineering" by S. K. Ghosh and S. B. Chatterjee.3.建筑施工中的结构设计与施工技术的英文参考文献"Structural Design for Buildings: Principles and Practice" by Robert H. Kuhn and David G. Alford."Structural Design of Buildings: An Integrated Approach" by B. R. Khanduri and C. P. Kumar."Structural Engineering in Architecture: Design and Application" by Ravi S. Sreedharan and Sivaprasad Sreekanth.4.桥梁工程中结构设计与施工技术的英文参考文献"Bridge Engineering: Design, Analysis, and Construction" by M. J. Rizzo and R. D. Lorenzetti."Bridge Engineering: Structural Design and Analysis" by D. Srivastava and K. Gupta."Bridge Design: Structural, Geometric, and Estimating" by B. Kundtz and D. Pritchard.5.岩土工程中结构设计与施工技术的英文参考文献"Geotechnical Engineering: Principles and Practices" by Hasanuddin Omar, Reinhard Rath, Ziadi Mat Saad and Erhard Becher"Soil Mechanics: Principles and Applications" by Yue Shu-xian and Fang Chao-ming"Foundation Engineering Handbook" by Adrain J Hogg, Ivor Richards, Graeme Barden, Clive Cussans and Mike O’Sullivan这些文献涵盖了土木工程中结构设计与施工技术的各个方面,从建筑设计到桥梁工程和岩土工程等。

土木工程英文参考文献

土木工程英文参考文献

Introduction to Civil Engineering PapersCivil Engineering for the development of a key role, first as a material foundation for the civil engineering construction materials, followed by the subsequent development of the design theory and construction technology. Every time a new quality of building materials, civil engineering will be a leap-style development.People can only rely on the early earth, wood and other natural materials in the construction activities, and later appeared in brick and tile that artificial materials, so that the first human to break the shackles of natural building materials. China in the eleventh century BC in the early Western Zhou Dynasty created the tile. The first brick in the fifth century BC to the third century BC, when the tomb of the Warring States Period. Brick and tile better than the mechanical properties of soil, materials, and easy to manufacture. The brick and tile so that people began to appear widely, to a large number of housing construction and urban flood control project, and so on. This civil engineering technology has been rapid development. Up to 18 to the 19th century, as long as two thousand years, brick and tile has been a major civil engineering construction materials, human civilization has made a great contribution to the even was also widely used in the present.The application of a large number of steel products is the second leap in civil engineering. Seventeen 1970s the use of pig iron, the early nineteenth century, the use of wrought iron bridges and the construction of housing, which is a prelude to the emergence of steel. From the beginning of the mid-nineteenth century, metallurgical industry, smelting and rolling out high tensile and compressive strength, ductility, uniformity of the quality of construction steel and then produce high-strength steel wire, steel cables. As a result of the need to adapt to the development of the steel structure have been flourishing. In addition to the application of the original beam, arch structure, the new truss, a framework, the structure of network, cable structures to promote the gradual emergence of the structure of Yan in the form of flowers.From the brick building long-span structures, stone structures, a few meters of wood, steel structure to the development of tens of meters, a few hundred meters, until modern km above. So in the river, cross the bridge from shelves, on the ground since the construction of skyscrapers and high-rise tower, even in the laying of underground railway, to create an unprecedented miracle.In order to meet the needs of the development of steel works, on the basis of Newton's mechanics, material mechanics, structural mechanics, structural engineering design theory came into being, and so on. Construction machinery, construction technology and construction organization design theory also development, civil engineering from the experience of rising to become science, engineering practice and theoretical basis for both is a different place, which led to more rapid development of civil engineering. During the nineteenth century, 20, made of Portland cement, concrete has come out. Concrete can aggregate materials, easy-to-concrete structures forming, but the tensile strength of concrete is very small, limited use. By the middle of the nineteenth century, the surge in steel production, with the emergence of this new type of reinforced concrete composite construction materials, which bear the tension steel, concrete bear the pressure and play their own advantages. Since the beginning of the 20th century,reinforced concrete is widely used in various fields of civil engineering.From the beginning of the 1930s, there have been pre-stressed concrete. Pre-stressed concrete structure of the crack resistance, rigidity and carrying capacity, much higher than the reinforced concrete structure, which uses an even wider area. Civil Engineering into the reinforced concrete and prestressed concrete dominant historical period. Concrete buildings to bring about the emergence of new economic, aesthetic structure in the form of engineering, civil engineering so that a new construction technology and engineering design of the structure of the theory. This is another leap in the development of civil engineering.A project to build the facilities in general to go through the investigation, design and construction in three stages, require the use of geological prospecting projects, hydro-geological survey, engineering survey, soil mechanics, mechanical engineering, engineering design, building materials, construction equipment, engineering machinery, building the economy , And other disciplines and construction technology, construction and other fields of knowledge, as well as computer and mechanical testing techniques. Civil engineering is therefore a broad range of integrated disciplines. With the progress in science and technology development and engineering practice, the civil engineering disciplines have also been developed into a broad connotation, the number of categories, the structure of complex integrated system.Civil Engineering is accompanied by the development of human society developed. It works in the construction of facilities reflect the various historical periods of socio-economic, cultural, scientific, technological development outlook, which civil society has become one of the historical development of the witness.In ancient times, people began to build simple houses, roads, bridges and still water channel to meet the simple life and production. Later, in order to adapt to the war, production and dissemination of religious life, as well as the needs of the construction of the city, canals, palaces, temples and other buildings.Many well-known works shown in this historical period of human creativity. For example, the Great Wall of China, Dujiangyan, the Grand Canal, Zhaozhou Bridge, Yingxian Wooden Tower, the pyramids of Egypt, Greece's Parthenon, Rome's water supply project, colosseum amphitheater (Rome large animal fighting Field), as well as many other well-known churches, palaces and so on.After the industrial revolution, especially in the 20th century, on the one hand, civil society to put forward a new demand; On the other hand, all areas of society for the advancement of civil engineering to create good conditions. Thus this period of civil engineering has been advanced by leaps and bounds. All over the world there have been large-scale modernization of industrial plants, skyscrapers, nuclear power plants, highways and railways, long-span bridges, and large-diameter pipelines long tunnel, the Grand Canal, the big dams, airports, port and marine engineering, etc. . For civil engineering continually modern human society to create a new physical environment, human society, modern civilization has become an important part.Civil Engineering is a very practical subjects. In the early days, through the civil engineering practice, summing up successful experience, in particular, to draw lessons from the failure of developed. From the beginning of the 17th century, with Galileo andNewton as a pilot with the mechanics of the modern civil engineering practice, gradually formed the mechanical, structural mechanics, fluid mechanics, rock mechanics, civil engineering as the basis of theoretical subjects. This experience in civil engineering from the gradually developed into a science.In the course of the development of civil engineering, engineering practice often first experience in theory, engineering accidents often show a new unforeseen factors, triggering a new theory of the research and development. So far a number of projects dealing with the problem, is still very much rely on practical experience.Civil Engineering Technology with the main reason for the development of engineering practice and not by virtue of scientific experiments and theoretical studies, for two reasons: First, some of the objective situation is too complicated and difficult to faithfully carry out laboratory or field testing and analysis. For example, the foundation, tunnel and underground engineering and deformation of the state and its changes over time, still need to refer to an analysis of engineering experience to judge. Second, only a new engineering practice in order to reveal new problems. For example, the construction of a high-rise buildings, high-rise tower and mast-span bridges, wind and earthquake engineering problems highlighted in order to develop this new theory and technology.In the long-term civil engineering practice, it is not only building great attention to the arts, has made outstanding achievements; and other works, but also through the choice of different materials, such as the use of stone, steel and reinforced concrete, with natural Environmental art in the construction of a number of very beautiful, very functional and good works. Ancient Great Wall of China, the modern world, many of the television tower and the bridge ramp Zhang, are cases in point.A building is closely bound up with people,for it provides with the necessary space to work and live in .As classified by their use ,buildings are mainly of two types :industrial buildings and civil buildings .industrial buildings are used by various factories or industrial production while civil buildings are those that are used by people for dwelling ,employment ,education and other social activities .Industrial buildings are factory buildings that are available for processing and manufacturing of various kinds ,in such fields as the mining industry ,the metallurgical industry ,machine building ,the chemical industry and the textile industry . factory buildings can be classified into two types single-story ones and multi-story ones .the construction of industrial buildings is the same as that of civil buildings .however ,industrial and civil buildings differ in the materials used and in the way they are used .Civil buildings are divided into two broad categories: residential buildings and public buildings .residential buildings should suit family life .each flat should consist of at least three necessary rooms : a living room ,a kitchen and a toilet .public buildings can be used in politics ,cultural activities ,administration work and other services ,such as schools, office buildings, parks ,hospitals ,shops ,stations ,theatres ,gymnasiums ,hotels ,exhibition halls ,bath pools ,and so on .all of them have different functions ,which in turn require different design types as well.Housing is the living quarters for human beings .the basic function of housing is to provide shelter from the elements ,but people today require much more that of theirhousing .a family moving into a new neighborhood will to know if the available housing meets its standards of safety ,health ,and comfort .a family will also ask how near the housing is to grain shops ,food markets ,schools ,stores ,the library ,a movie theater ,and the community center .In the mid-1960’s a most important value in housing was sufficient space both inside and out .a majority of families preferred single-family homes on about half an acre of land ,which would provide space for spare-time activities .in highly industrialized countries ,many families preferred to live as far out as possible from the center of a metropolitan area ,even if the wage earners had to travel some distance to their work .quite a large number of families preferred country housing to suburban housing because their chief aim was to get far away from noise ,crowding ,and confusion .the accessibility of public transportation had ceased to be a decisive factor in housing because most workers drove their cars to work .people we’re chiefly interested in the arrangement and size of rooms and the number of bedrooms .Before any of the building can begin ,plans have to be drawn to show what the building will be like ,the exact place in which it is to go and how everything is to be done.An important point in building design is the layout of rooms ,which should provide the greatest possible convenience in relation to the purposes for which they are intended .in a dwelling house ,the layout may be considered under three categories : “day”, “night” ,and “services” .attention must be paid to the provision of easy communication between these areas .the “day “rooms generally include a dining-room ,sitting-room and kitchen ,but other rooms ,such as a study ,may be added ,and there may be a hall .the living-room ,which is generally the largest ,often serves as a dining-room ,too ,or the kitchen may have a dining alcove .the “night “rooms consist of the bedrooms .the “services “comprise the kitchen ,bathrooms ,larder ,and water-closets .the kitchen and larder connect the services with the day rooms .It is also essential to consider the question of outlook from the various rooms ,and those most in use should preferably face south as possible .it is ,however ,often very difficult to meet the optimum requirements ,both on account of the surroundings and the location of the roads .in resolving these complex problems ,it is also necessary to follow the local town-planning regulations which are concerned with public amenities ,density of population ,height of buildings ,proportion of green space to dwellings ,building lines ,the general appearance of new properties in relation to the neighbourhood ,and so on . There is little standardization in industrial buildings although such buildings still need to comply with local town-planning regulations .the modern trend is towards light ,airy factory buildings .generally of reinforced concrete or metal construction ,a factory can be given a “shed ”type ridge roof ,incorporating windows facing north so as to give evenly distributed natural lighting without sun-glare .。

土木工程项目管理英文文献

土木工程项目管理英文文献

Abstract: This paper aims to discuss the importance of effective project management in civil engineering construction projects. It highlights the key aspects of project management such as planning, execution, and control. Furthermore, it provides insights into the challenges faced by project managers in civil engineering projects and suggests strategies to overcome these challenges. The paper also emphasizes the role of technology in improving project management efficiency.Introduction:Civil engineering construction projects are complex and involve multiple stakeholders, resources, and activities. Effective project management is crucial to ensure the successful completion of these projects within the specified time, budget, and quality standards. This paper explores the significance of effective project management in civil engineering construction projects and presents strategies to enhance project management practices.1. Key Aspects of Project Management in Civil Engineering Construction1.1 Planning:Proper planning is essential for the successful execution of civil engineering projects. This involves identifying project objectives, defining scope, estimating resources, and establishing a realistic timeline. A well-defined plan helps in allocating resources efficiently, minimizing risks, and ensuring project success.1.2 Execution:Once the plan is in place, project execution becomes the primary focus. This stage involves coordinating various activities, managing resources, and ensuring that the project progresses as per the plan. Effective communication, leadership, and teamwork are crucial during this phase.1.3 Control:Control is the process of monitoring and adjusting the projectactivities to ensure that they are aligned with the planned objectives. This includes tracking progress, identifying deviations, andimplementing corrective actions. Effective control helps in minimizing risks, avoiding cost overruns, and ensuring project quality.2. Challenges in Civil Engineering Project Management2.1 Stakeholder Management:Civil engineering projects involve various stakeholders, including clients, contractors, consultants, and regulatory authorities. Managing these stakeholders' expectations, concerns, and conflicts is a significant challenge for project managers.2.2 Resource Allocation:Resource allocation is another critical challenge in civil engineering projects. Ensuring that resources such as labor, materials, and equipment are available when needed requires effective planning and coordination.2.3 Time Constraints:Time constraints are common in civil engineering projects. Adhering to project schedules and meeting deadlines is essential for project success.3. Strategies to Overcome Challenges in Civil Engineering Project Management3.1 Effective Communication:Establishing clear and open communication channels among all stakeholders is crucial for effective project management. Regular updates, meetings, and feedback sessions help in addressing concerns and ensuring alignment with project objectives.3.2 Utilizing Technology:Leveraging technology can significantly improve project management efficiency. Tools like project management software, Building Information Modeling (BIM), and mobile applications can help in tracking progress, managing resources, and facilitating communication.3.3 Risk Management:Identifying potential risks and developing mitigation strategies is essential for successful project management. Conducting risk assessments, implementing risk mitigation plans, and monitoring risks throughout the project lifecycle can help in avoiding cost overruns and delays.Conclusion:Effective project management plays a vital role in the success of civil engineering construction projects. By addressing the key aspects of project management, overcoming challenges, and utilizing technology, project managers can ensure the timely completion of projects within budget and quality standards. This paper emphasizes the importance of effective project management in civil engineering construction and provides insights into strategies to enhance project management practices.。

土木工程类专业英文文献及翻译

土木工程类专业英文文献及翻译

土木工程类专业英文文献及翻译第一篇:土木工程类专业英文文献及翻译PAVEMENT PROBLEMS CAUSEDBY COLLAPSIBLE SUBGRADESBy Sandra L.Houston,1 Associate Member, ASCE(Reviewed by the Highway Division)ABSTRACT: Problem subgrade materials consisting of collapsible soils are com-mon in arid environments, which have climatic conditions and depositional and weathering processes favorable to their formation.Included herein is a discussion of predictive techniques that use commonly available laboratory equipment and testing methods for obtaining reliable estimates of the volume change for these problem soils.A method for predicting relevant stresses and corresponding collapse strains for typical pavement subgrades is presented.Relatively simple methods of evaluating potential volume change, based on results of familiar laboratory tests, are used.INTRODUCTION When a soil is given free access to water, it may decrease in volume,increase in volume, or do nothing.A soil that increases in volume is called a swelling or expansive soil, and a soil that decreases in volume is called a collapsible soil.The amount of volume change that occurs depends on the soil type and structure, the initial soil density, the imposed stress state, and the degree and extent of wetting.Subgrade materials comprised of soils that change volume upon wetting have caused distress to highways since the be-ginning of the professional practice and have cost many millions of dollars in roadway repairs.The prediction of the volume changes that may occur in the field is the first step in making an economic decision for dealing withthese problem subgrade materials.Each project will have different design considerations, economic con-straints, and risk factors that will have to be taken into account.However, with a reliable method for making volume change predictions, the best design relative to the subgrade soils becomes a matter of economic comparison, and a much more rational design approach may be made.For example, typical techniques for dealing with expansive clays include:(1)In situ treatments with substances such as lime, cement, or fly-ash;(2)seepage barriers and/ or drainage systems;or(3)a computing of the serviceability loss and a mod-ification of the design to “accept” the anticipated expansion.In order to make the most economical decision, the amount of volume change(especially non-uniform volume change)must be accurately estimated, and the degree of road roughness evaluated from these data.Similarly, alternative design techniques are available for any roadway problem.The emphasis here will be placed on presenting economical and simple methods for:(1)Determining whether the subgrade materials are collapsible;and(2)estimating the amount of volume change that is likely to occur in the 'Asst.Prof., Ctr.for Advanced Res.in Transp., Arizona State Univ., Tempe, AZ 85287.Note.Discussion open until April 1, 1989.To extend the closing date one month,a written request must be filed with the ASCE Manager of Journals.The manuscriptfor this paper was submitted for review and possible publication on February 3, 1988.This paper is part of the Journal of Transportation.Engineering, Vol.114, No.6,November, 1988.ASCE, ISSN 0733-947X/88/0006-0673/$1.00 + $.15 per page.Paper No.22902.673field for the collapsible soils.Then this information will place the engineerin a position to make a rational design decision.Collapsible soils are fre-quently encountered in an arid climate.The depositional process and for-mation of these soils, and methods for identification and evaluation of theamount of volume change that may occur, will be discussed in the followingsections.COLLAPSIBLE SOILSFormation of Collapsible SoilsCollapsible soils have high void ratios and low densities and are typicallycohesionless or only slightly cohesive.In an arid climate, evaporation greatlyexceeds rainfall.Consequently, only the near-surface soils become wettedfrom normal rainfall.It is the combination of the depositional process andthe climate conditions that leads to the formation of the collapsible soil.Although collapsible soils exist in nondesert regions, the dry environment inwhich evaporation exceeds precipitation is very favorable for the formationof the collapsible structure.As the soil dries by evaporation, capillary tension causes the remainingwater to withdraw into the soil grain interfaces, bringing with it soluble salts,clay, and silt particles.As the soil continues to dry, these salts, clays, andsilts come out of solution, and “tack-we ld” the larger grains together.Thisleads to a soil structure that has high apparent strength at its low, naturalwater content.However, collapse of the “cemented” structure may occurupon wetting because the bonding material weakens and softens, and the soilis unstable at any stress level that exceeds that at which the soil had beenpreviously wetted.Thus, if the amount of water made available to the soilis increased above that which naturally exists, collapse can occur at fairlylow levels of stress, equivalent only to overburden soil pressure.Additionalloads, such as traffic loading or the presence of a bridge structure, add tothe collapse, especially of shallow collapsible soil.The triggering mechanismfor collapse, however, is the addition of water.Highway Problems Resulting from Collapsible SoilsNonuniform collapse can result from either a nonhomogeneous subgradedeposit in which differing degrees of collapse potential exist and/or fromnonuniform wetting of subgrade materials.When differential collapse ofsubgrade soils occurs, the result is a rough, wavy surface, and potentiallymany miles of extensively damaged highway.There have been several re-ported cases for which differential collapse has been cited as the cause ofroadway or highway bridge distress.A few of these in the Arizona and NewMexico region include sections of 1-10 near Benson, Arizona, and sectionsof 1-25 in the vicinity of Algadonas, New Mexico(Lovelace et al.1982;Russman 1987).In addition to the excessive waviness of the roadway sur-face, bridge foundations failures, such as the Steins Pass Highway bridge,1-10, in Arizona, have frequently been identified with collapse of foundationsoils.Identification of Collapsible SoilsThere have been many techniques proposed for identifying a collapsiblesoil problem.These methods range from qualitative index tests conducted on4disturbed samples, to response to wetting tests conducted on relatively un-disturbed samples, to in situ meausrement techniques.In all cases, the en-gineer must first know if the soils may become wetted to a water contentabove their natural moisture state, and if so, what the extent of the potentialwetted zone will be.Most methods for identifying collapsible soils are onlyqualitative in nature, providing no information on the magnitude of the col-lapse strain potential.These qualitative methods are based on various func-tions of dry density, moisture content, void ratio, specific gravity, and At-terberg limits.In situ measurement methods appear promising in some cases, in that manyresearchers feel that sample disturbance is greatly reduced, and that a morenearly quantitative measure of collapse potential is obtainable.However,in situ test methods for collapsible soils typically suffer from the deficien-cy of an unknown extent and degree of wetting during the field test.Thismakes a quantitative measurement difficult because the zone of materialbeing influenced is not well-known, and, therefore, the actual strains, in-duced by the addition of stress and water, are not well-known.In addition,the degree of saturation achieved in the field test is variable and usuallyunknown.Based on recently conducted research, it appears that the most reliablemethod for identifying a collapsible soil problem is to obtain the best qualityundisturbed sample possible and to subject this sample to a response to wet-ting test in the laboratory.The results of a simple oedometer test will indicatewhether the soil is collapsible and, at the same time, give a direct measureof the amount of collapse strain potential that may occur in the field.Potentialproblems associated with the direct sampling method include sample distur-bance and the possibility that the degree of saturation achieved in the fieldwill be less than that achieved in the laboratory test.The quality of an undisturbed sample is related most strongly to the arearatio of the tube that is used for sample collection.The area ratio is a measureof the ratio of the cross-sectional area of the sample collected to the cross-sectional area of the sample tube.A thin-walled tube sampler by definitionhas an area ratio of about 10-15%.Although undisturbed samples are bestobtained through the use of thin-walled tube samplers, it frequently occursthat these stiff, cemented collapsible soils, especially those containing gravel,cannot be sampled unless a tube with a much thicker wall is used.Samplershaving an area ratio as great as 56% are commonly used for Arizona col-lapsible soils.Further, it may take considerable hammering of the tube todrive the sample.The result is, of course, some degree of sample distur-bance, broken.bonds, densification, and a correspondingly reduced collapsemeasured upon laboratory testing.However, for collapsible soils, which arecompressive by definition, the insertion of the sample tube leads to localshear failure at the base of the cutting edge, and, therefore, there is lesssample disturbance than would be expected for soils that exhibit general shearfailure(i.e., saturated clays or dilative soils).Results of an ongoing studyof sample disturbance for collapsible soils indicate that block samples some-times exhibit somewhat higher collapse strains compared to thick-walled tubesamples.Block samples are usually assumed to be the very best obtainableundisturbed samples, although they are frequently difficult-to-impossible toobtain, especially at substantial depths.The overall effect of sample distur-bance is a slight underestimate of the collapse potential for the soil.675译文:湿陷性地基引起的路面问题作者:...摘要:在干旱环境中,湿陷性土壤组成的路基材料是很常见的,干旱环境中的气候条件、沉积以及风化作用都有利于湿陷性土的形成。

(完整版)土木工程毕业设计外文文献翻译

(完整版)土木工程毕业设计外文文献翻译

外文文献翻译Reinforced ConcreteConcrete and reinforced concrete are used as building materials in every country. In many, including the United States and Canada, reinforced concrete is a dominant structural material in engineered construction. The universal nature of reinforced concrete construction stems from the wide availability of reinforcing bars and the constituents of concrete, gravel, sand, and cement, the relatively simple skills required in concrete construction, and the economy of reinforced concrete compared to other forms of construction. Concrete and reinforced concrete are used in bridges, buildings of all sorts underground structures, water tanks, television towers, offshore oil exploration and production structures, dams, and even in ships.Reinforced concrete structures may be cast-in-place concrete, constructed in their final location, or they may be precast concrete produced in a factory and erected at the construction site. Concrete structures may be severe and functional in design, or the shape and layout and be whimsical and artistic. Few other building materials off the architect and engineer such versatility and scope.Concrete is strong in compression but weak in tension. As a result, cracks develop whenever loads, or restrained shrinkage of temperature changes, give rise to tensile stresses in excess of the tensile strength of the concrete. In a plain concrete beam, the moments about the neutral axis due to applied loads are resisted by an internal tension-compression couple involving tension in the concrete. Such a beam fails very suddenly and completely when the first crack forms. In a reinforced concrete beam, steel bars are embedded in the concrete in such a way that the tension forces needed for moment equilibrium after the concrete cracks can be developed in the bars.The construction of a reinforced concrete member involves building a from of mold in the shape of the member being built. The form must be strong enough to support both the weight and hydrostatic pressure of the wet concrete, and any forces applied to it by workers, concrete buggies, wind, and so on. The reinforcement is placed in this form and held in placeduring the concreting operation. After the concrete has hardened, the forms are removed. As the forms are removed, props of shores are installed to support the weight of the concrete until it has reached sufficient strength to support the loads by itself.The designer must proportion a concrete member for adequate strength to resist the loads and adequate stiffness to prevent excessive deflections. In beam must be proportioned so that it can be constructed. For example, the reinforcement must be detailed so that it can be assembled in the field, and since the concrete is placed in the form after the reinforcement is in place, the concrete must be able to flow around, between, and past the reinforcement to fill all parts of the form completely.The choice of whether a structure should be built of concrete, steel, masonry, or timber depends on the availability of materials and on a number of value decisions. The choice of structural system is made by the architect of engineer early in the design, based on the following considerations:1. Economy. Frequently, the foremost consideration is the overall const of the structure. This is, of course, a function of the costs of the materials and the labor necessary to erect them. Frequently, however, the overall cost is affected as much or more by the overall construction time since the contractor and owner must borrow or otherwise allocate money to carry out the construction and will not receive a return on this investment until the building is ready for occupancy. In a typical large apartment of commercial project, the cost of construction financing will be a significant fraction of the total cost. As a result, financial savings due to rapid construction may more than offset increased material costs. For this reason, any measures the designer can take to standardize the design and forming will generally pay off in reduced overall costs.In many cases the long-term economy of the structure may be more important than the first cost. As a result, maintenance and durability are important consideration.2. Suitability of material for architectural and structural function.A reinforced concrete system frequently allows the designer to combine the architectural and structural functions. Concrete has the advantage that it is placed in a plastic condition and is given the desired shapeand texture by means of the forms and the finishing techniques. This allows such elements ad flat plates or other types of slabs to serve as load-bearing elements while providing the finished floor and / or ceiling surfaces. Similarly, reinforced concrete walls can provide architecturally attractive surfaces in addition to having the ability to resist gravity, wind, or seismic loads. Finally, the choice of size of shape is governed by the designer and not by the availability of standard manufactured members.3. Fire resistance. The structure in a building must withstand the effects of a fire and remain standing while the building is evacuated and the fire is extinguished. A concrete building inherently has a 1- to 3-hour fire rating without special fireproofing or other details. Structural steel or timber buildings must be fireproofed to attain similar fire ratings.4. Low maintenance.Concrete members inherently require less maintenance than do structural steel or timber members. This is particularly true if dense, air-entrained concrete has been used for surfaces exposed to the atmosphere, and if care has been taken in the design to provide adequate drainage off and away from the structure. Special precautions must be taken for concrete exposed to salts such as deicing chemicals.5. Availability of materials. Sand, gravel, cement, and concrete mixing facilities are very widely available, and reinforcing steel can be transported to most job sites more easily than can structural steel. As a result, reinforced concrete is frequently used in remote areas.On the other hand, there are a number of factors that may cause one to select a material other than reinforced concrete. These include:1. Low tensile strength.The tensile strength concrete is much lower than its compressive strength ( about 1/10 ), and hence concrete is subject to cracking. In structural uses this is overcome by using reinforcement to carry tensile forces and limit crack widths to within acceptable values. Unless care is taken in design and construction, however, these cracks may be unsightly or may allow penetration of water. When this occurs, water or chemicals such as road deicing salts may cause deterioration or staining of the concrete. Special design details are required in such cases. In the case of water-retaining structures, special details and /of prestressing are required to prevent leakage.2. Forms and shoring. The construction of a cast-in-place structure involves three steps not encountered in the construction of steel or timber structures. These are ( a ) the construction of the forms, ( b ) the removal of these forms, and (c) propping or shoring the new concrete to support its weight until its strength is adequate. Each of these steps involves labor and / or materials, which are not necessary with other forms of construction.3. Relatively low strength per unit of weight for volume.The compressive strength of concrete is roughly 5 to 10% that of steel, while its unit density is roughly 30% that of steel. As a result, a concrete structure requires a larger volume and a greater weight of material than does a comparable steel structure. As a result, long-span structures are often built from steel.4. Time-dependent volume changes. Both concrete and steel undergo-approximately the same amount of thermal expansion and contraction. Because there is less mass of steel to be heated or cooled, and because steel is a better concrete, a steel structure is generally affected by temperature changes to a greater extent than is a concrete structure. On the other hand, concrete undergoes frying shrinkage, which, if restrained, may cause deflections or cracking. Furthermore, deflections will tend to increase with time, possibly doubling, due to creep of the concrete under sustained loads.In almost every branch of civil engineering and architecture extensive use is made of reinforced concrete for structures and foundations. Engineers and architects requires basic knowledge of reinforced concrete design throughout their professional careers. Much of this text is directly concerned with the behavior and proportioning of components that make up typical reinforced concrete structures-beams, columns, and slabs. Once the behavior of these individual elements is understood, the designer will have the background to analyze and design a wide range of complex structures, such as foundations, buildings, and bridges, composed of these elements.Since reinforced concrete is a no homogeneous material that creeps, shrinks, and cracks, its stresses cannot be accurately predicted by the traditional equations derived in a course in strength of materials forhomogeneous elastic materials. Much of reinforced concrete design in therefore empirical, i.e., design equations and design methods are based on experimental and time-proved results instead of being derived exclusively from theoretical formulations.A thorough understanding of the behavior of reinforced concrete will allow the designer to convert an otherwise brittle material into tough ductile structural elements and thereby take advantage of concrete’s desirable characteristics, its high compressive strength, its fire resistance, and its durability.Concrete, a stone like material, is made by mixing cement, water, fine aggregate ( often sand ), coarse aggregate, and frequently other additives ( that modify properties ) into a workable mixture. In its unhardened or plastic state, concrete can be placed in forms to produce a large variety of structural elements. Although the hardened concrete by itself, i.e., without any reinforcement, is strong in compression, it lacks tensile strength and therefore cracks easily. Because unreinforced concrete is brittle, it cannot undergo large deformations under load and fails suddenly-without warning. The addition fo steel reinforcement to the concrete reduces the negative effects of its two principal inherent weaknesses, its susceptibility to cracking and its brittleness. When the reinforcement is strongly bonded to the concrete, a strong, stiff, and ductile construction material is produced. This material, called reinforced concrete, is used extensively to construct foundations, structural frames, storage takes, shell roofs, highways, walls, dams, canals, and innumerable other structures and building products. Two other characteristics of concrete that are present even when concrete is reinforced are shrinkage and creep, but the negative effects of these properties can be mitigated by careful design.A code is a set technical specifications and standards that control important details of design and construction. The purpose of codes it produce structures so that the public will be protected from poor of inadequate and construction.Two types f coeds exist. One type, called a structural code, is originated and controlled by specialists who are concerned with the proper use of a specific material or who are involved with the safe design of a particular class of structures.The second type of code, called a building code, is established to cover construction in a given region, often a city or a state. The objective of a building code is also to protect the public by accounting for the influence of the local environmental conditions on construction. For example, local authorities may specify additional provisions to account for such regional conditions as earthquake, heavy snow, or tornados. National structural codes genrally are incorporated into local building codes.The American Concrete Institute ( ACI ) Building Code covering the design of reinforced concrete buildings. It contains provisions covering all aspects of reinforced concrete manufacture, design, and construction. It includes specifications on quality of materials, details on mixing and placing concrete, design assumptions for the analysis of continuous structures, and equations for proportioning members for design forces.All structures must be proportioned so they will not fail or deform excessively under any possible condition of service. Therefore it is important that an engineer use great care in anticipating all the probable loads to which a structure will be subjected during its lifetime.Although the design of most members is controlled typically by dead and live load acting simultaneously, consideration must also be given to the forces produced by wind, impact, shrinkage, temperature change, creep and support settlements, earthquake, and so forth.The load associated with the weight of the structure itself and its permanent components is called the dead load. The dead load of concrete members, which is substantial, should never be neglected in design computations. The exact magnitude of the dead load is not known accurately until members have been sized. Since some figure for the dead load must be used in computations to size the members, its magnitude must be estimated at first. After a structure has been analyzed, the members sized, and architectural details completed, the dead load can be computed more accurately. If the computed dead load is approximately equal to the initial estimate of its value ( or slightly less ), the design is complete, but if a significant difference exists between the computed and estimated values of dead weight, the computations should be revised using an improved value of dead load. An accurate estimate of dead load is particularly important when spans are long, say over 75 ft ( 22.9 m ),because dead load constitutes a major portion of the design load.Live loads associated with building use are specific items of equipment and occupants in a certain area of a building, building codes specify values of uniform live for which members are to be designed.After the structure has been sized for vertical load, it is checked for wind in combination with dead and live load as specified in the code. Wind loads do not usually control the size of members in building less than 16 to 18 stories, but for tall buildings wind loads become significant and cause large forces to develop in the structures. Under these conditions economy can be achieved only by selecting a structural system that is able to transfer horizontal loads into the ground efficiently.钢筋混凝土在每一个国家,混凝土及钢筋混凝土都被用来作为建筑材料。

土木工程外文文献及翻译

土木工程外文文献及翻译

本科毕业设计外文文献及译文文献、资料题目:Designing Against Fire Of Building 文献、资料来源:国道数据库文献、资料发表(出版)日期:2008.3.25院(部):土木工程学院专业:土木工程班级:土木辅修091姓名:xxxx外文文献:Designing Against Fire Of BulidingxxxABSTRACT:This paper considers the design of buildings for fire safety. It is found that fire and the associ- ated effects on buildings is significantly different to other forms of loading such as gravity live loads, wind and earthquakes and their respective effects on the building structure. Fire events are derived from the human activities within buildings or from the malfunction of mechanical and electrical equipment provided within buildings to achieve a serviceable environment. It is therefore possible to directly influence the rate of fire starts within buildings by changing human behaviour, improved maintenance and improved design of mechanical and electrical systems. Furthermore, should a fire develops, it is possible to directly influence the resulting fire severity by the incorporation of fire safety systems such as sprinklers and to provide measures within the building to enable safer egress from the building. The ability to influence the rate of fire starts and the resulting fire severity is unique to the consideration of fire within buildings since other loads such as wind and earthquakes are directly a function of nature. The possible approaches for designing a building for fire safety are presented using an example of a multi-storey building constructed over a railway line. The design of both the transfer structure supporting the building over the railway and the levels above the transfer structure are considered in the context of current regulatory requirements. The principles and assumptions associ- ated with various approaches are discussed.1 INTRODUCTIONOther papers presented in this series consider the design of buildings for gravity loads, wind and earthquakes.The design of buildings against such load effects is to a large extent covered by engineering based standards referenced by the building regulations. This is not the case, to nearly the same extent, in the case of fire. Rather, it is building regulations such as the Building Code of Australia (BCA) that directly specify most of the requirements for fire safety of buildings with reference being made to Standards such as AS3600 or AS4100 for methods for determining the fire resistance of structural elements.The purpose of this paper is to consider the design of buildings for fire safety from an engineering perspective (as is currently done for other loads such as wind or earthquakes), whilst at the same time,putting such approaches in the context of the current regulatory requirements.At the outset,it needs to be noted that designing a building for fire safety is far morethan simply considering the building structure and whether it has sufficient structural adequacy.This is because fires can have a direct influence on occupants via smoke and heat and can grow in size and severity unlike other effects imposed on the building. Notwithstanding these comments, the focus of this paper will be largely on design issues associated with the building structure.Two situations associated with a building are used for the purpose of discussion. The multi-storey office building shown in Figure 1 is supported by a transfer structure that spans over a set of railway tracks. It is assumed that a wide range of rail traffic utilises these tracks including freight and diesel locomotives. The first situation to be considered from a fire safety perspective is the transfer structure.This is termed Situation 1 and the key questions are: what level of fire resistance is required for this transfer structure and how can this be determined? This situation has been chosen since it clearly falls outside the normal regulatory scope of most build- ing regulations. An engineering solution, rather than a prescriptive one is required. The second fire situation (termed Situation 2) corresponds to a fire within the office levels of the building and is covered by building regulations. This situation is chosen because it will enable a discussion of engineering approaches and how these interface with the building regulations–since both engineering and prescriptive solutions are possible.2 UNIQUENESS OF FIRE2.1 IntroductionWind and earthquakes can be considered to b e “natural” phenomena over which designers have no control except perhaps to choose the location of buildings more carefully on the basis of historical records and to design building to resist sufficiently high loads or accelerations for the particular location. Dead and live loads in buildings are the result of gravity. All of these loads are variable and it is possible (although generally unlikely) that the loads may exceed the resistance of the critical structural members resulting in structural failure.The nature and influence of fires in buildings are quite different to those associated with other“loads” to which a building may be subjected to. The essential differences are described in the following sections.2.2 Origin of FireIn most situations (ignoring bush fires), fire originates from human activities within the building or the malfunction of equipment placed within the building to provide a serviceable environment. It follows therefore that it is possible to influence the rate of fire starts by influencing human behaviour, limiting and monitoring human behaviour and improving thedesign of equipment and its maintenance. This is not the case for the usual loads applied to a building.2.3 Ability to InfluenceSince wind and earthquake are directly functions of nature, it is not possible to influence such events to any extent. One has to anticipate them and design accordingly. It may be possible to influence the level of live load in a building by conducting audits and placing restrictions on contents. However, in the case of a fire start, there are many factors that can be brought to bear to influence the ultimate size of the fire and its effect within the building. It is known that occupants within a building will often detect a fire and deal with it before it reaches a sig- nificant size. It is estimated that less than one fire in five (Favre, 1996) results in a call to the fire brigade and for fires reported to the fire brigade, the majority will be limited to the room of fire origin. In oc- cupied spaces, olfactory cues (smell) provide powerful evidence of the presence of even a small fire. The addition of a functional smoke detection system will further improve the likelihood of detection and of action being taken by the occupants.Fire fighting equipment, such as extinguishers and hose reels, is generally provided within buildings for the use of occupants and many organisations provide training for staff in respect of the use of such equipment.The growth of a fire can also be limited by automatic extinguishing systems such as sprinklers, which can be designed to have high levels of effectiveness.Fires can also be limited by the fire brigade depending on the size and location of the fire at the time of arrival. 2.4 Effects of FireThe structural elements in the vicinity of the fire will experience the effects of heat. The temperatures within the structural elements will increase with time of exposure to the fire, the rate of temperature rise being dictated by the thermal resistance of the structural element and the severity of the fire. The increase in temperatures within a member will result in both thermal expansion and,eventually,a reduction in the structural resistance of the member. Differential thermal expansion will lead to bowing of a member. Significant axial expansion will be accommodated in steel members by either overall or local buckling or yielding of local- ised regions. These effects will be detrimental for columns but for beams forming part of a floor system may assist in the development of other load resisting mechanisms (see Section 4.3.5).With the exception of the development of forces due to restraint of thermal expansion, fire does not impose loads on the structure but rather reduces stiffness and strength. Such effects are not instantaneous but are a function of time and this is different to the effects of loads such as earthquake and wind that are more or less instantaneous.Heating effects associated with a fire will not be significant or the rate of loss of capacity will be slowed if:(a) the fire is extinguished (e.g. an effective sprinkler system)(b) the fire is of insufficient severity – insufficient fuel, and/or(c)the structural elements have sufficient thermal mass and/or insulation to slow the rise in internal temperatureFire protection measures such as providing sufficient axis distance and dimensions for concrete elements, and sufficient insulation thickness for steel elements are examples of (c). These are illustrated in Figure 2.The two situations described in the introduction are now considered.3 FIRE WITHIN BUILDINGS3.1 Fire Safety ConsiderationsThe implications of fire within the occupied parts of the office building (Figure 1) (Situation 2) are now considered. Fire statistics for office buildings show that about one fatality is expected in an office building for every 1000 fires reported to the fire brigade. This is an order of magnitude less than the fatality rate associated with apartment buildings. More than two thirds of fires occur during occupied hours and this is due to the greater human activity and the greater use of services within the building. It is twice as likely that a fire that commences out of normal working hours will extend beyond the enclosure of fire origin.A relatively small fire can generate large quantities of smoke within the floor of fire origin. If the floor is of open-plan construction with few partitions, the presence of a fire during normal occupied hours is almost certain to be detected through the observation of smoke on the floor. The presence of full height partitions across the floor will slow the spread of smoke and possibly also the speed at which the occupants detect the fire. Any measures aimed at improving housekeeping, fire awareness and fire response will be beneficial in reducing thelikelihood of major fires during occupied hours.For multi-storey buildings, smoke detection systems and alarms are often provided to give “automatic” detection and warning to the occupants. An alarm signal is also transmitted to the fire brigade.Should the fire not be able to be controlled by the occupants on the fire floor, they will need to leave the floor of fire origin via the stairs. Stair enclosures may be designed to be fire-resistant but this may not be sufficient to keep the smoke out of the stairs. Many buildings incorporate stair pressurisation systems whereby positive airflow is introduced into the stairs upon detection of smoke within the building. However, this increases the forces required to open the stair doors and makes it increasingly difficult to access the stairs. It is quite likely that excessive door opening forces will exist(Fazio et al,2006)From a fire perspective, it is common to consider that a building consists of enclosures formed by the presence of walls and floors.An enclosure that has sufficiently fire-resistant boundaries (i.e. walls and floors) is considered to constitute a fire compartment and to be capable of limiting the spread of fire to an adjacent compartment. However, the ability of such boundaries to restrict the spread of fire can be severely limited by the need to provide natural lighting (windows)and access openings between the adjacent compartments (doors and stairs). Fire spread via the external openings (windows) is a distinct possibility given a fully developed fire. Limit- ing the window sizes and geometry can reduce but not eliminate the possibility of vertical fire spread.By far the most effective measure in limiting fire spread, other than the presence of occupants, is an effective sprinkler system that delivers water to a growing fire rapidly reducing the heat being generated and virtually extinguishing it.3.2 Estimating Fire SeverityIn the absence of measures to extinguish developing fires, or should such systems fail; severe fires can develop within buildings.In fire en gineering literature, the term “fire load” refers to the quantity of combustibles within an enclosure and not the loads (forces) applied to the structure during a fire. Similarly, fire load density refers to the quantity of fuel per unit area. It is normally expressed in terms of MJ/m2 or kg/m2 of wood equivalent. Surveys of combustibles for various occupancies (i.e offices, retail, hospitals, warehouses, etc)have been undertaken and a good summary of the available data is given in FCRC (1999). As would be expected, the fire load density is highly variable. Publications such as the International Fire Engineering Guidelines (2005) give fire load data in terms of the mean and 80th percentile.The latter level of fire load density is sometimes taken asthe characteristic fire load density and is sometimes taken as being distributed according to a Gumbel distribution (Schleich et al, 1999).The rate at which heat is released within an enclosure is termed the heat release rate (HRR) and normally expressed in megawatts (MW). The application of sufficient heat to a combustible material results in the generation of gases some of which are combustible. This process is called pyrolisation.Upon coming into contact with sufficient oxygen these gases ignite generating heat. The rate of burning(and therefore of heat generation) is therefore dependent on the flow of air to the gases generated by the pyrolising fuel.This flow is influenced by the shape of the enclosure (aspect ratio), and the position and size of any potential openings. It is found from experiments with single openings in approximately cubic enclosures that the rate of burning is directly proportional to A h where A is the area of the opening and h is the opening height. It is known that for deep enclosures with single openings that burning will occur initially closest to the opening moving back into the enclosure once the fuel closest to the opening is consumed (Thomas et al, 2005). Significant temperature variations throughout such enclosures can be expected.The use of the word ‘opening’ in relation to real building enclosures refers to any openings present around the walls including doors that are left open and any windows containing non fire-resistant glass.It is presumed that such glass breaks in the event of development of a significant fire. If the windows could be prevented from breaking and other sources of air to the enclosure limited, then the fire would be prevented from becoming a severe fire.Various methods have been developed for determining the potential severity of a fire within an enclosure.These are described in SFPE (2004). The predictions of these methods are variable and are mostly based on estimating a representative heat release rate (HRR) and the proportion of total fuel ςlikely to be consumed during the primary burning stage (Figure 4). Further studies of enclosure fires are required to assist with the development of improved models, as the behaviour is very complex.3.3 Role of the Building StructureIf the design objectives are to provide an adequate level of safety for the occupants and protection of adjacent properties from damage, then the structural adequacy of the building in fire need only be sufficient to allow the occupants to exit the building and for the building to ultimately deform in a way that does not lead to damage or fire spread to a building located on an adjacent site.These objectives are those associated with most building regulations includingthe Building Code of Australia (BCA). There could be other objectives including protection of the building against significant damage. In considering these various objectives, the following should be taken into account when considering the fire resistance of the building structure.3.3.1 Non-Structural ConsequencesSince fire can produce smoke and flame, it is important to ask whether these outcomes will threaten life safety within other parts of the building before the building is compromised by a loss of structural adequacy? Is search and rescue by the fire brigade not feasible given the likely extent of smoke? Will the loss of use of the building due to a severe fire result in major property and income loss? If the answer to these questions is in the affirmative, then it may be necessary to minimise the occurrence of a significant fire rather than simply assuming that the building structure needs to be designed for high levels of fire resistance. A low-rise shopping centre with levels interconnected by large voids is an example of such a situation.3.3.2 Other Fire Safety SystemsThe presence of other systems (e.g. sprinklers) within the building to minimise the occurrence of a serious fire can greatly reduce the need for the structural elements to have high levels of fire resistance. In this regard, the uncertainties of all fire-safety systems need to be considered. Irrespective of whether the fire safety system is the sprinkler system, stair pressurisation, compartmentation or the system giving the structure a fire-resistance level (e.g. concrete cover), there is an uncertainty of performance. Uncertainty data is available for sprinkler systems(because it is relatively easy to collect) but is not readily available for the other fire safety systems. This sometimes results in the designers and building regulators considering that only sprinkler systems are subject to uncertainty. In reality, it would appear that sprinklers systems have a high level of performance and can be designed to have very high levels of reliability.3.3.3 Height of BuildingIt takes longer for a tall building to be evacuated than a short building and therefore the structure of a tall building may need to have a higher level of fire resistance. The implications of collapse of tall buildings on adjacent properties are also greater than for buildings of only several storeys.3.3.4 Limited Extent of BurningIf the likely extent of burning is small in comparison with the plan area of the building, then the fire cannot have a significant impact on the overall stability of the building structure. Examples of situations where this is the case are open-deck carparks and very large area building such as shopping complexes where the fire-effected part is likely to be small in relation to area of the building floor plan.3.3.5 Behaviour of Floor ElementsThe effect of real fires on composite and concrete floors continues to be a subject of much research.Experimental testing at Cardington demonstrated that when parts of a composite floor are subject to heating, large displacement behaviour can develop that greatly assists the load carrying capacity of the floor beyond that which would predicted by considering only the behaviour of the beams and slabs in isolation.These situations have been analysed by both yield line methods that take into account the effects of membrane forces (Bailey, 2004) and finite element techniques. In essence, the methods illustrate that it is not necessary to insulate all structural steel elements in a composite floor to achieve high levels of fire resistance.This work also demonstrated that exposure of a composite floor having unprotected steel beams, to a localised fire, will not result in failure of the floor.A similar real fire test on a multistory reinforced concrete building demonstrated that the real structural behaviour in fire was significantly different to that expected using small displacement theory as for normal tempera- ture design (Bailey, 2002) with the performance being superior than that predicted by considering isolated member behaviour.3.4 Prescriptive Approach to DesignThe building regulations of most countries provide prescriptive requirements for the design of buildings for fire.These requirements are generally not subject to interpretation and compliance with them makes for simpler design approval–although not necessarily the most cost-effective designs.These provisions are often termed deemed-to-satisfy (DTS) provisions. All aspects of designing buildings for fire safety are covered–the provision of emergency exits, spacings between buildings, occupant fire fighting measures, detection and alarms, measures for automatic fire suppression, air and smoke handling requirements and last, but not least, requirements for compartmentation and fire resistance levels for structural members. However, there is little evidence that the requirements have been developed from a systematic evaluation of fire safety. Rather it would appear that many of the requirements have been added one to another to deal with another fire incident or to incorporate a new form of technology. There does not appear to have been any real attempt to determine which provision have the most significant influence on fire safety and whether some of the former provisions could be modified.The FRL requirements specified in the DTS provisions are traditionally considered to result in member resistances that will only rarely experience failure in the event of a fire.This is why it is acceptable to use the above arbitrary point in time load combination for assessing members in fire. There have been attempts to evaluate the various deemed-to-satisfy provisions (particularly the fire- resistance requirements)from a fire-engineering perspective taking intoaccount the possible variations in enclosure geometry, opening sizes and fire load (see FCRC, 1999).One of the outcomes of this evaluation was the recognition that deemed-to- satisfy provisions necessarily cover the broad range of buildings and thus must, on average, be quite onerous because of the magnitude of the above variations.It should be noted that the DTS provisions assume that compartmentation works and that fire is limited to a single compartment. This means that fire is normally only considered to exist at one level. Thus floors are assumed to be heated from below and columns only over one storey height.3.5 Performance-Based DesignAn approach that offers substantial benefits for individual buildings is the move towards performance-based regulations. This is permitted by regulations such as the BCA which state that a designer must demonstrate that the particular building will achieve the relevant performance requirements. The prescriptive provisions (i.e. the DTS provisions) are presumed to achieve these requirements. It is necessary to show that any building that does not conform to the DTS provisions will achieve the performance requirements.But what are the performance requirements? Most often the specified performance is simply a set of performance statements (such as with the Building Code of Australia)with no quantitative level given. Therefore, although these statements remind the designer of the key elements of design, they do not, in themselves, provide any measure against which to determine whether the design is adequately safe.Possible acceptance criteria are now considered.3.5.1 Acceptance CriteriaSome guidance as to the basis for acceptable designs is given in regulations such as the BCA. These and other possible bases are now considered in principle.(i)compare the levels of safety (with respect to achieving each of the design objectives) of the proposed alternative solution with those asso- ciated with a corresponding DTS solution for the building.This comparison may be done on either a qualitative or qualitative risk basis or perhaps a combination. In this case, the basis for comparison is an acceptable DTS solution. Such an approach requires a “holistic” approach to safety whereby all aspects relevant to safety, including the structure, are considered. This is, by far, the most common basis for acceptance.(ii)undertake a probabilistic risk assessment and show that the risk associated with the proposed design is less than that associated with common societal activities such as using pub lic transport. Undertaking a full probabilistic risk assessment can be very difficult for all but the simplest situations.Assuming that such an assessment is undertaken it will be necessary for the stakeholders to accept the nominated level of acceptable risk. Again, this requires a “holistic”approach to fire safety.(iii) a design is presented where it is demonstrated that all reasonable measures have been adopted to manage the risks and that any possible measures that have not been adopted will have negligible effect on the risk of not achieving the design objectives.(iv) as far as the building structure is concerned,benchmark the acceptable probability of failure in fire against that for normal temperature design. This is similar to the approach used when considering Building Situation 1 but only considers the building structure and not the effects of flame or smoke spread. It is not a holistic approach to fire safety.Finally, the questions of arson and terrorism must be considered. Deliberate acts of fire initiation range from relatively minor incidents to acts of mass destruction.Acts of arson are well within the accepted range of fire events experienced by build- ings(e.g. 8% of fire starts in offices are deemed "suspicious"). The simplest act is to use a small heat source to start a fire. The resulting fire will develop slowly in one location within the building and will most probably be controlled by the various fire- safety systems within the building. The outcome is likely to be the same even if an accelerant is used to assist fire spread.An important illustration of this occurred during the race riots in Los Angeles in 1992 (Hart 1992) when fires were started in many buildings often at multiple locations. In the case of buildings with sprinkler systems,the damage was limited and the fires significantly controlled.Although the intent was to destroy the buildings,the fire-safety systems were able to limit the resulting fires. Security measures are provided with systems such as sprinkler systems and include:- locking of valves- anti-tamper monitoring- location of valves in secure locationsFurthermore, access to significant buildings is often restricted by security measures.The very fact that the above steps have been taken demonstrates that acts of destruction within buildings are considered although most acts of arson do not involve any attempt to disable the fire-safety systems.At the one end of the spectrum is "simple" arson and at the other end, extremely rare acts where attempts are made to destroy the fire-safety systems along with substantial parts of the building.This can be only achieved through massive impact or the use of explosives. The latter may be achieved through explosives being introduced into the building or from outside by missile attack.The former could result from missile attack or from the collision of a large aircraft. The greater the destructiveness of the act,the greater the means and knowledge required. Conversely, the more extreme the act, the less confidence there can be in designing against suchan act. This is because the more extreme the event, the harder it is to predict precisely and the less understood will be its effects. The important point to recognise is that if sufficient means can be assembled, then it will always be possible to overcome a particular building design.Thus these acts are completely different to the other loadings to which a building is subjected such as wind,earthquake and gravity loading. This is because such acts of destruction are the work of intelligent beings and take into account the characteristics of the target.Should high-rise buildings be designed for given terrorist activities,then terrorists will simply use greater means to achieve the end result.For example, if buildings were designed to resist the impact effects from a certain size aircraft, then the use of a larger aircraft or more than one aircraft could still achieve destruction of the building. An appropriate strategy is therefore to minimise the likelihood of means of mass destruction getting into the hands of persons intent on such acts. This is not an engineering solution associated with the building structure.It should not be assumed that structural solutions are always the most appropriate, or indeed, possible.In the same way, aircrafts are not designed to survive a major fire or a crash landing but steps are taken to minimise the likelihood of either occurrence.The mobilization of large quantities of fire load (the normal combustibles on the floors) simultaneously on numerous levels throughout a building is well outside fire situations envisaged by current fire test standards and prescriptive regulations. Risk management measures to avoid such a possibility must be considered.4 CONCLUSIONSFire differs significantly from other “loads” such as wind, live load and earthquakes i n respect of its origin and its effects.Due to the fact that fire originates from human activities or equipment installed within buildings, it is possible to directly influence the potential effects on the building by reducing the rate of fire starts and providing measures to directly limit fire severity.The design of buildings for fire safety is mostly achieved by following the prescriptive requirements of building codes such as the BCA. For situations that fall outside of the scope of such regulations, or where proposed designs are not in accordance with the prescriptive requirements, it is possible to undertake performance-based fire engineering designs.However, there are no design codes or standards or detailed methodologies available for undertaking such designs.Building regulations require that such alternative designs satisfy performance requirements and give some guidance as to the basis for acceptance of these designs (i.e. acceptance criteria).This paper presents a number of possible acceptance criteria, all of which use the measure of risk level as the basis for comparison.Strictly, when considering the risks。

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Introduction to Civil Engineering PapersCivil Engineering for the development of a key role, first as a material foundation for the civil engineering construction materials, followed by the subsequent development of the design theory and construction technology. Every time a new quality of building materials, civil engineering will be a leap-style development.People can only rely on the early earth, wood and other natural materials in the construction activities, and later appeared in brick and tile that artificial materials, so that the first human to break the shackles of natural building materials. China in the eleventh century BC in the early Western Zhou Dynasty created the tile. The first brick in the fifth century BC to the third century BC, when the tomb of the Warring States Period. Brick and tile better than the mechanical properties of soil, materials, and easy to manufacture. The brick and tile so that people began to appear widely, to a large number of housing construction and urban flood control project, and so on. This civil engineering technology has been rapid development. Up to 18 to the 19th century, as long as two thousand years, brick and tile has been a major civil engineering construction materials, human civilization has made a great contribution to the even was also widely used in the present.The application of a large number of steel products is the second leap in civil engineering. Seventeen 1970s the use of pig iron, the early nineteenth century, the use of wrought iron bridges and the construction of housing, which is a prelude to the emergence of steel. From the beginning of the mid-nineteenth century, metallurgical industry, smelting and rolling out high tensile and compressive strength, ductility, uniformity of the quality of construction steel and then produce high-strength steel wire, steel cables. As a result of the need to adapt to the development of the steel structure have been flourishing. In addition to the application of the original beam, arch structure, the new truss, a framework, the structure of network, cable structures to promote the gradual emergence of the structure of Yan in the form of flowers.From the brick building long-span structures, stone structures, a few meters of wood, steel structure to the development of tens of meters, a few hundred meters, until modern km above. So in the river, cross the bridge from shelves, on the ground since the construction of skyscrapers and high-rise tower, even in the laying of underground railway, to create an unprecedented miracle.In order to meet the needs of the development of steel works, on the basis of Newton's mechanics, material mechanics, structural mechanics, structural engineering design theory came into being, and so on. Construction machinery, construction technology and construction organization design theory also development, civil engineering from the experience of rising to become science, engineering practice and theoretical basis for both is a different place, which led to more rapid development of civil engineering. During the nineteenth century, 20, made of Portland cement, concrete has come out. Concrete can aggregate materials, easy-to-concrete structures forming, but the tensile strength of concrete is very small, limited use. By the middle of the nineteenth century, the surge in steel production, with the emergence of this new type of reinforced concrete composite construction materials, which bear the tension steel, concrete bear the pressure and play their own advantages. Since the beginning of the 20th century,reinforced concrete is widely used in various fields of civil engineering.From the beginning of the 1930s, there have been pre-stressed concrete. Pre-stressed concrete structure of the crack resistance, rigidity and carrying capacity, much higher than the reinforced concrete structure, which uses an even wider area. Civil Engineering into the reinforced concrete and prestressed concrete dominant historical period. Concrete buildings to bring about the emergence of new economic, aesthetic structure in the form of engineering, civil engineering so that a new construction technology and engineering design of the structure of the theory. This is another leap in the development of civil engineering.A project to build the facilities in general to go through the investigation, design and construction in three stages, require the use of geological prospecting projects, hydro-geological survey, engineering survey, soil mechanics, mechanical engineering, engineering design, building materials, construction equipment, engineering machinery, building the economy , And other disciplines and construction technology, construction and other fields of knowledge, as well as computer and mechanical testing techniques. Civil engineering is therefore a broad range of integrated disciplines. With the progress in science and technology development and engineering practice, the civil engineering disciplines have also been developed into a broad connotation, the number of categories, the structure of complex integrated system.Civil Engineering is accompanied by the development of human society developed. It works in the construction of facilities reflect the various historical periods of socio-economic, cultural, scientific, technological development outlook, which civil society has become one of the historical development of the witness.In ancient times, people began to build simple houses, roads, bridges and still water channel to meet the simple life and production. Later, in order to adapt to the war, production and dissemination of religious life, as well as the needs of the construction of the city, canals, palaces, temples and other buildings.Many well-known works shown in this historical period of human creativity. For example, the Great Wall of China, Dujiangyan, the Grand Canal, Zhaozhou Bridge, Yingxian Wooden Tower, the pyramids of Egypt, Greece's Parthenon, Rome's water supply project, colosseum amphitheater (Rome large animal fighting Field), as well as many other well-known churches, palaces and so on.After the industrial revolution, especially in the 20th century, on the one hand, civil society to put forward a new demand; On the other hand, all areas of society for the advancement of civil engineering to create good conditions. Thus this period of civil engineering has been advanced by leaps and bounds. All over the world there have been large-scale modernization of industrial plants, skyscrapers, nuclear power plants, highways and railways, long-span bridges, and large-diameter pipelines long tunnel, the Grand Canal, the big dams, airports, port and marine engineering, etc. . For civil engineering continually modern human society to create a new physical environment, human society, modern civilization has become an important part.Civil Engineering is a very practical subjects. In the early days, through the civil engineering practice, summing up successful experience, in particular, to draw lessons from the failure of developed. From the beginning of the 17th century, with Galileo andNewton as a pilot with the mechanics of the modern civil engineering practice, gradually formed the mechanical, structural mechanics, fluid mechanics, rock mechanics, civil engineering as the basis of theoretical subjects. This experience in civil engineering from the gradually developed into a science.In the course of the development of civil engineering, engineering practice often first experience in theory, engineering accidents often show a new unforeseen factors, triggering a new theory of the research and development. So far a number of projects dealing with the problem, is still very much rely on practical experience.Civil Engineering Technology with the main reason for the development of engineering practice and not by virtue of scientific experiments and theoretical studies, for two reasons: First, some of the objective situation is too complicated and difficult to faithfully carry out laboratory or field testing and analysis. For example, the foundation, tunnel and underground engineering and deformation of the state and its changes over time, still need to refer to an analysis of engineering experience to judge. Second, only a new engineering practice in order to reveal new problems. For example, the construction of a high-rise buildings, high-rise tower and mast-span bridges, wind and earthquake engineering problems highlighted in order to develop this new theory and technology.In the long-term civil engineering practice, it is not only building great attention to the arts, has made outstanding achievements; and other works, but also through the choice of different materials, such as the use of stone, steel and reinforced concrete, with natural Environmental art in the construction of a number of very beautiful, very functional and good works. Ancient Great Wall of China, the modern world, many of the television tower and the bridge ramp Zhang, are cases in point.A building is closely bound up with people,for it provides with the necessary space to work and live in .As classified by their use ,buildings are mainly of two types :industrial buildings and civil buildings .industrial buildings are used by various factories or industrial production while civil buildings are those that are used by people for dwelling ,employment ,education and other social activities .Industrial buildings are factory buildings that are available for processing and manufacturing of various kinds ,in such fields as the mining industry ,the metallurgical industry ,machine building ,the chemical industry and the textile industry . factory buildings can be classified into two types single-story ones and multi-story ones .the construction of industrial buildings is the same as that of civil buildings .however ,industrial and civil buildings differ in the materials used and in the way they are used .Civil buildings are divided into two broad categories: residential buildings and public buildings .residential buildings should suit family life .each flat should consist of at least three necessary rooms : a living room ,a kitchen and a toilet .public buildings can be used in politics ,cultural activities ,administration work and other services ,such as schools, office buildings, parks ,hospitals ,shops ,stations ,theatres ,gymnasiums ,hotels ,exhibition halls ,bath pools ,and so on .all of them have different functions ,which in turn require different design types as well.Housing is the living quarters for human beings .the basic function of housing is to provide shelter from the elements ,but people today require much more that of theirhousing .a family moving into a new neighborhood will to know if the available housing meets its standards of safety ,health ,and comfort .a family will also ask how near the housing is to grain shops ,food markets ,schools ,stores ,the library ,a movie theater ,and the community center .In the mid-1960’s a most important value in housing was sufficient space both inside and out .a majority of families preferred single-family homes on about half an acre of land ,which would provide space for spare-time activities .in highly industrialized countries ,many families preferred to live as far out as possible from the center of a metropolitan area ,even if the wage earners had to travel some distance to their work .quite a large number of families preferred country housing to suburban housing because their chief aim was to get far away from noise ,crowding ,and confusion .the accessibility of public transportation had ceased to be a decisive factor in housing because most workers drove their cars to work .people we’re chiefly interested in the arrangement and size of rooms and the number of bedrooms .Before any of the building can begin ,plans have to be drawn to show what the building will be like ,the exact place in which it is to go and how everything is to be done.An important point in building design is the layout of rooms ,which should provide the greatest possible convenience in relation to the purposes for which they are intended .in a dwelling house ,the layout may be considered under three categories : “day”, “night” ,and “services” .attention must be paid to the provision of easy communication between these areas .the “day “rooms generally include a dining-room ,sitting-room and kitchen ,but other rooms ,such as a study ,may be added ,and there may be a hall .the living-room ,which is generally the largest ,often serves as a dining-room ,too ,or the kitchen may have a dining alcove .the “night “rooms consist of the bedrooms .the “services “comprise the kitchen ,bathrooms ,larder ,and water-closets .the kitchen and larder connect the services with the day rooms .It is also essential to consider the question of outlook from the various rooms ,and those most in use should preferably face south as possible .it is ,however ,often very difficult to meet the optimum requirements ,both on account of the surroundings and the location of the roads .in resolving these complex problems ,it is also necessary to follow the local town-planning regulations which are concerned with public amenities ,density of population ,height of buildings ,proportion of green space to dwellings ,building lines ,the general appearance of new properties in relation to the neighbourhood ,and so on . There is little standardization in industrial buildings although such buildings still need to comply with local town-planning regulations .the modern trend is towards light ,airy factory buildings .generally of reinforced concrete or metal construction ,a factory can be given a “shed ”type ridge roof ,incorporating windows facing north so as to give evenly distributed natural lighting without sun-glare .。

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