结构稳定理论之钢结构设计论文英文版
论钢结构设计中稳定问题
论钢结构设计中的稳定问题【摘要】钢结构中的稳定问题是钢结构设计中以待解决的主要问题，一旦出现了钢结构的失稳事故，不但对经济造成严重的损失，而且会造成人员的伤亡。
本文介绍了钢结构稳定设计的基本概念，分析了钢结构稳定设计和施工原则。
【关键词】钢结构，稳定设计，施工原则【 abstract 】 steel in the stability problem is steel structure design of the main problems for solving, once appear, the steel structure of the instability accident, not only for the economy caused heavy losses, but also caused the personnel casualties. this paper introduces the design of the steel structure stability basic concept, this paper analyzes the design and construction of steel structure stability principle.【 key words 】 steel structure, stable design, construction principle中图分类号：s611文献标识码：a 文章编号：现代工程史上不乏因失稳而造成的钢结构事故，其中影响最大的是1907 年加拿大魁北克一座大桥在施工中破坏， 9000 吨钢结构全部坠入河中，桥上施工的人员75 人遇难。
破坏是由于悬臂的受压下弦失稳造成的。
而美国哈特福特城的体育馆网架结构，平面92m x 110m,突然于 1978年破坏而落地，破坏起因可能是压杆屈曲。
以及1988 年加拿大一停车场的屋盖结构塌落， 1985 年土耳其某体育场看台屋盖塌落，这两次事故都和没有设置适当的支撑有关。
钢结构桥梁中英文对照外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)Recent Research and Design Developments in Steel and Composite Steel-concrete Structures in USAThe paper will conclude with a look toward the future of structural steel research.1. Research on steel bridgesThe American Association of State Transportation and Highway Officials (AASTHO) is the authority that promulgates design standards for bridges in the US. In 1994 it has issued a new design specification which is a Limit States Design standard that is based on the principles of reliability theory. A great deal of work went into the development of this code in the past decade, especially on calibration and on the probabilistic evaluation of the previous specification. The code is now being implemented in the design office, together with the introduction of the SystemeInternationale units. Many questions remain open about the new method of design, and there are many new projects that deal with the reliability studies of the bridge as a system. One such current project is a study to develop probabilistic models, load factors, and rational load-combination rules for the combined effects of live-load and wind; live-load and earthquake; live-load, wind and ship collision; and ship collision, wind, and scour. There are also many field measurements of bridge behavior, using modern tools of inspection and monitoring such as acoustic emission techniques and other means of non-destructive evaluation. Such fieldwork necessitates parallel studies in the laboratory, and the evolution of ever more sophisticated high-technology data transmission methods.America has an aging steel bridge population and many problems arise from fatigue and corrosion. Fatigue studies on full-scale components of the Williamsburg Bridge in New York have recently been completed at Lehigh University. A probabilistic AASTHO bridge evaluation regulation has been in effect since 1989, and it is employed to assess the future useful life of structures using rational methods that include field observation and measurement together with probabilistic analysis. Such an activity also fosters additional research because many issues are still unresolved. One such area is the study of the shakedown of shear connectors in composite bridges. This work has been recently completed at the University of Missouri.In addition to fatigue and corrosion, the major danger to bridges is the possibility of earthquake induced damage. This also has spawned many research projects on the repair and retrofit of steel superstructures and the supporting concrete piers. Many bridges in the country are being strengthened for earthquake resistance. One area that is receiving much research attention is the strengthening of concrete piers by "jacketing" them by sheets of high-performance reinforced plastic.The previously described research deals mainly with the behavior of existing structures and the design of new bridges. However, there is also a vigorous activity on novel bridge systems. This research is centered on the application of high-performance steels for the design of innovative plate and box-girder bridges, such as corrugated webs, combinations of open and closed shapes, and longer spansfor truss bridges. It should be mentioned here that, in addition to work on steel bridges, there is also very active research going on in the study of the behavior of prestressed concrete girders made from very high strength concrete. The performance and design of smaller bridges using pultruded high-performance plastic composite members is also being studied extensively at present. New continuous bridge systems with steel concrete composite segments in both the positive moment and the negative moment regions are being considered. Several researchers have developed strong capabilities to model the three-dimensional non-linear behavior of individual plate girders, and many studies are being performed on the buckling and post-buckling characteristics of such panion experimental studies are also made,especially on members built from high-performance steels. A full-scale bridge of such steel has been designed, and will soon be constructed and then tested under traffic loading. Research efforts are also underway on the study of the fatigue of large expansion joint elements and on the fatigue of highway sign structures.The final subject to be mentioned is the resurgence of studies of composite steel concrete horizontally curved steel girder bridges. A just completed project at the University of Minnesota monitored the stresses and the deflections in a skewed and curved bridge during all phases of construction, starting from the fabrication yard to the completed bridge.~ Excellent correlation was found to exist between the measured stresses and deformations and the calculated values. The stresses and deflections during construction were found to be relatively small, that is, the construction process did not cause severe trauma to the system. The bridge has now been tested under service loading, using fully loaded gravel trucks, for two years, and it will continue to be studied for further years to measure changes in performance under service over time. A major testing project is being conducted at the Federal Highway Administration laboratory in Washington, DC, where a half-scale curved composite girder bridge is currently being tested to determine its limit states. The test-bridge was designed to act as its own test-frame, where various portions can be replaced after testing. Multiple flexure tests, shear tests, and tests under combined bending and shear, are thus performed with realistic end-conditions and restraints. The experiments arealso modeled by finite element analysis to check conformance between reality and prediction. Finally design standards will be evolved from the knowledge gained. This last project is the largest bridge research project in the USA at the present time.From the discussion above it can be seen that even though there is no large expansion of the nation's highway and railroad system, there is extensive work going on in bridge research. The major challenge facing both the researcher and the transportation engineer is the maintenance of a healthy but aging system, seeing to its gradual replacement while keeping it safe and serviceable.2. Research on steel members and framesThere are many research studies on the strength and behavior of steel building structures. The most important of these have to do with the behavior and design of steel structures under severe seismic events. This topic will be discussed later in this paper. The most significant trends of the non-seismic research are the following: "Advanced" methods of structural analysis and design are actively studied at many Universities, notably at Cornell, Purdue, Stanford, and Georgia Tech Universities. Such analysis methods are meant to determine the load-deformation behavior of frames up to and beyond failure, including inelastic behavior, force redistribution, plastic hinge formation, second-order effects and frame instability. When these methods are fully operational, the structure will not have to undergo a member check, because the finite element analysis of the frame automatically performs this job. In addition to the research on the best approaches to do this advanced analysis, there are also many studies on simplifications that can be easily utilized in the design office while still maintaining the advantages of a more complex analysis. The advanced analysis method is well developed for in-plane behavior, but much work is yet to be done on the cases where bi-axial bending or lateraltorsional buckling must be considered. Some successes have been achieved, but the research is far from complete.Another aspect of the frame behavior work is the study of the frames with semirigid joints. The American Institute of Steel Construction (AISC) has published design methods for office use. Current research is concentrating on the behavior ofsuch structures under seismic loading. It appears that it is possible to use such frames in some seismic situations, that is, frames under about 8 to 10 stories in height under moderate earthquake loads. The future of structures with semi-rigid frames looks very promising, mainly because of the efforts of researchers such as Leon at Georgia Tech University, and many others.Research on member behavior is concerned with studying the buckling and post buckling behavior of compact angle and wide-flange beam members by advanced commercial finite element programs. Such research is going back to examine the assumptions made in the 1950s and 1960s when the plastic design compactness and bracing requirements were first formulated on a semi-empirical basis. The non-linear finite element computations permit the "re-testing" of the old experiments and the performing of new computer experiments to study new types of members and new types of steels. White of Georgia Tech is one of the pioneers in this work. Some current research at the US military Academy and at the University of Minnesota by Earls is discussed later in this report. The significance of this type of research is that the phenomena of extreme yielding and distortion can be efficiently examined in parameter studies performed on the computer. The computer results can be verified with old experiments, or a small number of new experiments. These studies show a good prospect fornew insights into old problems that heretofore were never fully solved.3. Research on cold-formed steel structuresNext to seismic work, the most active part of research in the US is on cold-formed steel structures. The reason for this is that the supporting industry is expanding, especially in the area of individual family dwellings. As the cost of wood goes up, steel framed houses become more and more economical. The intellectual problems of thin-walled structures buckling in multiple modes under very large deformations have attracted some of the best minds in stability research. As a consequence, many new problems have been solved: complex member stiffening systems, stability and bracing of C and Z beams, composite slabs, perforated columns, standing-seam roof systems, bracing and stability of beams with very complicatedshapes, cold-formed members with steels of high yield stress-to-tensile strength ratio, and many other interesting applications. The American Iron and Steel Institute (AISI) has issued a new expanded standard in 1996 that brought many of these research results into the hands of the designer.4. Research on steel-concrete composite structuresAlmost all structural steel bridges and buildings in the US are built with composite beams or girders. In contrast, very few columns are built as composite members. The area of composite Column research is very active presently to fill up the gap of technical information on the behavior of such members. The subject of steel tubes filled with high-strength concrete is especially active. One of the aims of research performed by Hajjar at the University of Minnesota is to develop a fundamental understanding of the various interacting phenomena that occur in concrete-filled columns and beam-columns under monotonic and cyclic load. The other aim is to obtain a basic understanding of the behavior of connections of wide-flange beams to concrete filled tubes.Other major research work concerns the behavior and design of built-up composite wide-flange bridge girders under both positive and negative bending. This work is performed by Frank at the University of Texas at Austin and by White of Georgia Tech, and it involves extensive studies of the buckling and post-buckling of thin stiffened webs. Already mentioned is the examination of the shakedown of composite bridges. The question to be answered is whether a composite bridge girder loses composite action under repeated cycles of loads which are greater than the elastic limit load and less than the plastic mechanism load. A new study has been initiated at the University of Minnesota on the interaction between a semi-rigid steel frame system and a concrete shear wall connected by stud shear connectors.5. Research on connectionsConnection research continues to interest researchers because of the great variety of joint types. The majority of the connection work is currently related to the seismic problems that will be discussed in the next section of this paper. The most interest in non-seismic connections is the characterization of the monotonic moment-rotationbehavior of various types of semi-rigid joints.6. Research on structures and connections subject to seismic forcesThe most compelling driving force for the present structural steel research effort in the US was the January 17, 1994 earthquake in Northridge, California, North of Los Angeles. The major problem for steel structures was the extensive failure of prequalified welded rigid joints by brittle fracture. In over 150 buildings of one to 26 stories high there were over a thousand fractured joints. The buildings did not collapse, nor did they show any external signs of distress, and there were no human injuries or deaths. A typical joint is shown in Fig. 2.2.1.In this connection the flanges of the beams are welded to the flanges of the column by full-penetration butt welds. The webs are bolted to the beams and welded to the columns. The characteristic features of this type of connection are the backing bars at the bottom of the beam flange, and the cope-holes left open to facilitate the field welding of the beam flanges. Fractures occurred in the welds, in the beam flanges, and/or in the column flanges, sometimes penetrating into the webs.Once the problem was discovered several large research projects were initiated at various university laboratories, such as The University of California at San Diego, the University of Washington in Seattle, the University of Texas at Austin, Lehigh University at Bethlehem, Pennsylvania, and at other places. The US Government under the leadership of the Federal Emergency Management Agency (FEMA) instituted a major national research effort. The needed work was deemed so extensivethat no single research agency could hope to cope with it. Consequently three California groups formed a consortium which manages the work:(1) Structural Engineering Association of California.(2) Applied Technology Council.(3) California Universities for Research in Earthquake Engineering.The first letters in the name of each agency were combined to form the acronym SAC, which is the name of the joint venture that manages the research. We shall read much from this agency as the results of the massive amounts of research performed under its aegis are being published in the next few years.The goals of the program are to develop reliable, practical and cost-effective guidelines for the identification and inspection of at-risk steel moment frame buildings, the repair or upgrading of damaged buildings, the design of new construction, and the rehabilitation of undamaged buildings.~ As can be seen, the scope far exceeds the narrow look at the connections only. The first phase of the research was completed at the end of 1996, and its main aim was to arrive at interim guidelines so that design work could proceed. It consisted of the following components:~ A state-of-the-art assessment of knowledge on steel connections.~ A survey of building damage.~ The evaluation of ground motion.~ Detailed building analyses and case studies.~ A preliminary experimental program.~ Professional training and quality assurance programs.~ Publishing of the Interim Design Guidelines.A number of reports were issued in this first phase of the work. A partial list of these is appended at the end of this paper.During the first phase of the SAC project a series of full-scale connection tests under static and, occasionally, dynamic cyclic tests were performed. Tests were of pre-Northridge-type connections (that is, connections as they existed at the time of the earthquake), of repaired and upgraded details, and of new recommendedconnection details. A schematic view of the testing program is illustrated in Fig.2.2.2 Some recommended strategies for new design are schematically shown in Fig. 2.2.3.Fig. 2.2.3 some recommended improvements in the interim guidelinesThe following possible causes, and their combinations, were found to have contributed to tile connection failures:~ Inadequate workmanship in the field welds.~ Insufficient notch-toughness of the weld metal.~ Stress raisers caused by the backing bars.~ Lack of complete fusion near the backing bar.~ Weld bead sizes were too big.~ Slag inclusion in the welds.While many of the failures can be directly attributed to the welding and thematerial of the joints, there are more serious questions relative to the structural system that had evolved over the years mainly based on economic considerations.' The structural system used relatively few rigid-frames of heavy members that were designed to absorb the seismic forces for large parts of the structure. These few lateral-force resistant frames provide insufficient redundancy. More rigid-frames with smaller members could have provided a tougher and more ductile structural system. There is a question of size effect: Test results from joints of smaller members were extrapolated to joints with larger members without adequate test verification. The effect of a large initial pulse may have triggered dynamic forces that could have caused brittle fracture in joints with fracture critical details and materials. Furthermore, the yield stress of the beams was about 30% to 40% larger than the minimum specified values assumed in design, and so the connection failed before the beams, which were supposed to form plastic hinges.As can be seen, there are many possible reasons for this massive failure rate, and there is blame to go around for everyone. No doubt, the discussion about why and how the joints failed will go on for many more years. The structural system just did not measure up to demands that were more severe than expected. What should be kept in mind, however, is that no structure collapsed or caused even superficial nonstructural damage, and no person was injured or killed. In the strictest sense the structure sacrificed itself so that no physical harm was done to its users. The economic harm, of course, was enormous.7. Future directions of structural steel research and conclusionThe future holds many challenges for structural steel research. The ongoing work necessitated by the two recent earthquakes that most affected conventional design methods, namely, the Northridge earthquake in the US and the Kobe earthquake in Japan, will continue well into the first decade of the next Century. It is very likely that future disasters of this type will bring yet other problems to the steel research community. There is a profound change in the philosophy of design for disasters: We can no longer be content with saving lives only, but we must also design structures which will not be so damaged as to require extensive repairs.Another major challenge will be the emergence of many new materials such as high-performance concrete and plastic composite structures. Steel structures will continually have to face the problem of having to demonstrate viability in the marketplace. This can only be accomplished by more innovative research. Furthermore, the new comprehensive limit-states design codes which are being implemented worldwide, need research to back up the assumptions used in the theories.Specifically, the following list highlights some of the needed research in steel structures:Systems reliability tools have been developed to a high degree of sophistication. These tools should be applied to the studies of bridge and building structures to define the optimal locations of monitoring instruments, to assess the condition and the remaining life of structures, and to intelligently design economic repair and retrofit operations.New developments in instrumentation, data transfer and large-scale computation will enable researchers to know more about the response of structures under severe actions, so that a better understanding of "real-life" behavior can be achieved.The state of knowledge about the strength of structures is well above the knowledge about serviceability and durability. Research is needed on detecting and preventing damage in service and from deterioration.The areas of fatigue and fracture mechanics on the one hand, and the fields of structural stability on the other hand, should converge into a more Unified conceptual entity.The problems resulting from the combination of inelastic stability and low-cycle fatigue in connections subject to severe cyclic loads due to seismic action will need to be solved.The performance of members, connections and connectors (e.g., shear connectors) under severe cyclic and dynamic loading requires extensive new research, including shakedown behavior.The list could go on, but one should never be too dogmatic about the future ofsuch a highly creative activity as research. Nature, society and economics will provide sufficient challenges for the future generation of structural engineers.近期美国在钢结构和钢筋混凝土结构研究和设计方面的发展这篇文章将总结对钢结构的研究展望.1.钢结构桥梁的研究美国国家运输和公路官员协会(AASTH0)是为美国桥梁发布设计标准的权威。
Tekla Structure在钢结构设计中的应用
Tekla Structure在钢结构设计中的应用I. 序言- 简要介绍Tekla Structure在钢结构设计中的应用- 引出本论文的研究目的和意义II. Tekla Structure的概述- Tekla Structure的主要功能和特点- Tekla Structure在钢结构设计中的应用范围- Tekla Structure与其他建模软件的比较III. Tekla Structure在钢结构设计中的具体应用- Tekla Structure在钢结构模型的建立和修改中的应用- Tekla Structure在施工图绘制和钢构件加工中的应用- Tekla Structure在钢结构施工和安装中的应用IV. Tekla Structure的优势和不足- Tekla Structure在钢结构设计中的优势和优点- Tekla Structure在钢结构设计中的不足和待完善之处- Tekla Structure在未来的发展方向和趋势V. 总结与展望- 总结本论文的研究内容和结论- 展望Tekla Structure在钢结构设计中的未来发展和应用前景VI. 参考文献- 对本论文中引用的相关文献进行归纳和整理第一章序言随着建筑业的快速发展，新型建筑结构材料和设计方式的不断出现，钢结构设计越来越受到人们的关注。
而在钢结构设计中，使用先进的建模软件可以提高设计效率和准确性，减少错误率。
Tekla Structure作为三维建模软件的代表之一，已经在钢结构设计中广泛应用。
然而，目前对于Tekla Structure在钢结构设计中的应用还缺乏系统和深入的研究，本论文旨在探讨Tekla Structure在钢结构设计中的具体应用，分析其优势和不足，并展望其未来的发展方向和趋势。
第二章 Tekla Structure的概述2.1 Tekla Structure的主要功能和特点Tekla Structure是建筑和工程项目中广泛使用的一种三维建模软件，可以用于设计和建立钢结构、混凝土结构等各种类型的建筑结构。
钢结构的英文作文
钢结构的英文作文Steel structures are widely used in modern construction due to their strength and durability. They provide a strong framework for buildings, bridges, and other structures, and can withstand harsh weather conditions.The use of steel structures has revolutionized the construction industry, allowing for the creation of taller, more complex buildings. The versatility of steel allows for innovative and creative designs that would not be possible with traditional building materials.One of the key advantages of steel structures is their ability to be prefabricated off-site and then assembled on-site. This can significantly reduce construction time and costs, making steel structures a cost-effective option for many projects.Steel structures are also environmentally friendly, as they are often made from recycled materials and can berecycled at the end of their lifespan. This makes them a sustainable choice for construction projects.In addition to their strength and durability, steel structures also offer flexibility in terms of modifications and expansions. They can easily accommodate changes in design or function, making them a practical choice for buildings that may need to adapt to future needs.Overall, steel structures have become an integral part of modern construction, offering strength, durability, and versatility for a wide range of projects. Their use has transformed the way we build and has opened up new possibilities for architectural design and construction.。
建筑钢结构稳定设计[论文]
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试论建筑钢结构的稳定设计摘要随着建筑类经济快速的发展，工业建筑应用钢结构的越来越多。
防止结构失稳，是钢结构设计中应充分注意的问题。
本文阐述了钢结构的特性及在建筑上的应用，并对其稳定性的设计进行分析，根据设计经验进行总结，为后续设计施工提供技术支持。
关键词刚结构稳定性设计中图分类号：s611 文献标识码：a工业建筑钢结构的稳定问题在设计中，设计人员应该注重结构构件的稳定性能，以免在设计过程中发生不必要的失稳损失；其次，随着新型结构的出现，设计人员对其性能认识的不足，从而导致构件的失稳，就这个问题阐述了新型结构现存的问题，并且针对问题论述了产生的原因。
1建筑钢结构的稳定性设计钢结构的稳定性设计、在各种类型的钢结构中，由于结构失稳造成的伤亡事故时有发生、为了更好地保证钢结构稳定设计中构件不失稳定，保证工程质量及使用安全，有必要对钢结构的稳定性设计进行详细探讨。
1.1钢结构稳定性的概念钢结构强度小或失稳都会造成结构破坏，但是强度与稳定的概念并不相同、钢结构的强度是一个应力问题，指结构或者单个构件在稳定平衡状态下由荷载引起的最大应力（或内力）是否超过建筑材料的极限强度、钢材以其屈服点作为极限强度、而稳定是一个变形问题，构件所受外部荷载与结构内部抵抗力间是不稳定的，关键是找出这一不稳定的平衡状态，避免变形急剧增长而发生失稳破坏。
1.2钢结构稳定性设计要点（1）钢结构布置必须从体系和各组成部分的稳定性要求整体考虑，目前钢结构大多是按照平面体系进行设计，如桁架和框架、保证平面结构不出现平面外失稳，要求平面结构构件的平面稳定计算需与结构布置相一致，如增加必要的支撑构件等。
（2）实用计算方法所依据的简图与结构计算简图保持一致，中层或多层框架结构设计框架稳定分析通常是省略的，只进行框架柱的稳定计算，由于框架各柱的杆件稳定计算的常用力法、稳定参数等是依据一定的简化典型情况或假设者得出的，因此设计者要能保证所有的条件符合假设时才能应用。
钢结构抗震中英文对照外文翻译文献
中英文对照外文翻译(文档含英文原文和中文翻译)原文:Application of ACM Brace Retrofitting Countermeasure to Steel Structure AbstractAn advanced seismic retrofitting work for steel building structure with a doubtful seismic performance using ACM (Advanced Composite Material) bracing method, which consists of CFRP (Carbon Fiber Reinforced Plastic) rod and steel sleeve, was proposed in this paper. In order to save a lot of residents’ lives against a large-damaged earthquake, the retrofitting work using ACM bracing method to steel story building structure built by an old earthquake resistant design code was conducted. ACM bracing method was more economically and quickly applied to steel two-story building structures in comparison with the steel K -shaped bracing method used as before. This kind of retrofitting countermeasure will lead to an extreme decrease in earthquake damages for the existing old steel building structures built by some old earthquake resistant design codes.1. IntroductionIt is well known in Japan that a lot of reinforced concrete story buildings built by some old earthquake resistant design codes before 1981 were destroyed in the 1995 Hyogoken NanbuEarthquake. Therefore, Japanese Government has adopted several significant politics concerning this issue since 1995 in order to reduce a lot of earthquake damages for RC and steel story building structures (referred to as S building) built before 1981 as quickly as possible. As some seismic retrofitting policies adopted by Japanese Government had been not carried out smoothly, Japanese Government has been demanding a numerical target to quickly improve a seismic retrofitting ratio for all buildings by many local self-governments in Japan. This numerical target of seismic retrofitting ratio including RC and S buildings as well as wooden houses is 90% until 2017.In general, a seismic retrofitting work for RC and S building structure using a typical steel brace requires not only a large amount of cost but also the residents' removal or temporary evacuation. It is more desirable and convenient for a lot of RC and S building owners that the seismic retrofitting work is conducted as quickly and economically as possible. It is therefore very important for structural engineer to propose a new retrofitting technique instead of X and K shape steel braces. At the present time, a seismic resistant performance of RC or S building structure is judged from a seismic index of structure, Is, evaluated by some criteria established by the Japan building disaster prevention association (Housing Bureau in the Ministry of Land, Transport and Tourism in Japan 2001; Japanese Structural Engineer Association 2006). The number of steel brace required for the seismic retrofitting work of RC and S building structures can be decided to satisfy a given seismic judgment index value, Iso.The author has already proposed a seismic retrofitting countermeasure for RC building structure using an advanced composite material (referred to as ACM) bracing method (Takatani 2008 and Takatani 2011), which consists of a carbon fiber reinforced plastic (referred to as CFRP) material, steel sleeves and anchors, in order to save a lot of residents’ lives against a large-damaged earthquake. It is well known that CFRP material has several advantages of strong and light-weight feature, good durability, and wide applicability in comparison with the steel material. In this paper, ACM bracing method is applied for the seismic retrofitting work of S two-story building structure instead of steel bracing method.2.Seismic Retrofitting Work using ACM BracingHeretofore, the steel bracing method has been used for the seismic retrofitting work of RC and S building structures in Japan. The steel brace as shown in Figure 1 (a) is used on the outside of RC building, and is usually done in the inside of structure. While, Figure 1(b) shows ACM brace installed on the outside of structure. It is more desirable and very important for a lot of RC building structure owners that an earthquake resistant reinforcement work for RC building structure can be conducted as quickly and economically as possible ,and also can be done without residents’ removal or temporary evacuation. The seismic retrofitting work conducted on the outside of RC building structure shown in Figure 1 may be more convenient for both the residents in RC buildings and their owners. It is, therefore, very important for structural engineer to propose a new seismic retrofitting technique instead of the steel brace technique under conditions with low cost and short construction period.(a)Steel brace (b) ACM braceFigure 1. Sketch for seismic retrofitting works using steel brace and ACM brace ACM bracing method was proposed in order to aim at both low cost and short construction period in comparison with the steel bracing method. ACM bracing method consists of CFRP rod and CFRP sheet, steel sleeve, and steel anchor. Figure 2 shows ACM brace rod including CFRP rod and steel sleeve for ACM bracing method. The length 600mm of steel sleeve was decided from CFRP rod pull-out experiments from steel circular cylinder sleeve, and also can bear about 500 kN pull-out force. While, CFRP rods with various diameters are shown in Figure 3, and the material properties for CFRP rod is indicated in Table 1. The diameter of CFRP rod used for ACM bracing method is 10mm, and its tensile strength is 169.5 kN. Accordingly, three CFRP rods with 10mm diameter can bear about 500kN pull-out force. An advanced Epoxy resin developed by Konishi Co. Ltd. was employed for bonding between CFRP rods and steel cylinder sleeve (Horii 2007).Figure 4 indicates steel anchors embedded in RC column, and the anchor diameter and length were decided from pull-out experiment under 500 kN shear force. Figure 5 shows steel cylinder sleeve and nuts for the ACM bracing, whose pull-out bearing capacity is about 500 kN Hisabe (2007). Also, the CFRP rod of the ACM bracing is shown in Figure 6, and the length of the CFRP rod is 500m required for ACM bracing method applied to RC 3 -story building structure. Figure 7 indicates a CFRP sheet used to make a reinforcement of RC column against tensile force due to earthquake motions.Figure 2. ACM brace using CFRP rodFigure 3. CFRP rod (Intended Type, Mitsubishi Plastics Co. Ltd.)Figure 4. Anchors for ACM brace Figure 5. Steel sleeves for ACM braceFigure 6.CFRP rod (VΦ10mm,5@100m) Figure 7. CFRP sheet for ACM brace RC column surface around an anchor was pasted and covered with four CFRP sheet layers with different directions taking into consideration a tensile force direction.Figure 8. Elevation view of RC building with the ACM braceFigure 8 illustrates two typical elevations for the seismic retrofitting work using ACM bracing method. As the anchor embedment point in Plan A shown in Figure 8 (a) is located at the intersection area of RC column and beam where many reinforcing steel bars in RC column and beam gather around, it may be not so easy for a boring workman to make an anchor hole for ACM bracing method without cutting the reinforcing steel bars in this intersection area. Therefore, PlanB shown in Figure 8 (b) was proposed instead of Plan A, and the anchor embedment point avoidsthe intersection area of RC column and beam. In addition, it is found that the static deformation ofRC building structure in Plan B is smaller than that in Plan A through the structural analyses for both Plan A and B. This is because that the rigid part around the intersection area of RC column and beam is usually assumed on the structural analysis. Conforming to custom on structural analysis, this rigid part around the intersection area is defined by the width of RC column or beam (Aoyama 1988).Figure 9 indicates RC 3-story structure retrofitted by ACM braces (Takatani 2008 and Takatani 2011). After the installation of ACM brace, the steel anchor and sleeve were treated witha tarnish preventive. After this work, the steel cover was fixed on RC column surface as shown in Figure 9. After covering work of ACM brace, the final painting work was conducted and the covering box was made waterproof.Figure 9. Completion of ACM braces3.Application of ACM Brace to Steel StructureThe seismic retrofitting work using ACM bracing method was conducted for S two-story structure shown in Figure 5. Figure 5 shows the floor plan and the elevation view of this S structure. The number of ACM brace is decided by the seismic index of structure, Is, evaluated by some criteria established by the Japan building disaster prevention association in 2001 (Housing Bureau in the Ministry of Land, Transport and Tourism in Japan 2001). The seismic index of structure, Is, must satisfy a given seismic judgment index value, Iso, of the seismic index of structure. In this case, the seismic judgment index value, Iso, is 0.7.Figure 10. Floor plan and elevation viewTable 2 shows the seismic index of structure, Is, of the S building structure. It can be seen from Table 2 that the seismic index value of structure, Is, of the first floor in X direction is less than the seismic judgment index value, Iso =0.7, and the seismic index values of structure, Is, in Y directionare more than Iso =0.7. According to the seismic index values of structure, Is es are located on the east side and the west one of this S structure.Next, the construction process of this ACM bracing method is described. Figure 11 shows steel anchor fixed on steel column, and the anchor size was decided from pull-out experiment under 500kN shear force. Figure 12 indicates steel cylinder sleeves for ACM brace, whose pull-out bearing capacity is about 500kN and length is 600mm.Figure 11. Anchors for ACM braceFigure 12. Steel sleeves for ACM braceFigure 12 shows a bracket fixed on steel column, and the steel column before ACM brace installation work is indicated in Figure 14. Figure 15 illustrates polishing work on the surface of steel column by a grinder before welding work of bracket. The welding work of bracket by a welder is shown in Figure 16. Figure 17 and 18 show a bracket fixed on steel column by the welding work. Figure 19 indicates steel anchor fixed on a bracket by the welding work.Figure 13. Steel bracket for ACM braceFigure 15. Polishing work on steel column before welding work of steel bracketFigure 16. Welding work of steel bracket and a welder Figure 17. Completion of welding work of steel bracketFigure 18. Bracket after welding work Figure 19. Steel anchor after welding workFigure 20. CFRP rod cutting work Figure 21. Steel sleeve with three CFRP rodsFigure 22. Steel sleeves before Epoxy resin Figure 23. Epoxy resin injection work into steel Injection sleevesFigure 20 indicates a cutting work of CRFP rod by a saw, and three CFRP rods are installed into each steel sleeve as shown in Figure 21. Figure 22 indicates steel sleeves before Epoxy resin injection work, and Epoxy resin injection work into steel sleeve is shown in Figure 23. Figure24shows steel sleeves after Epoxy resin injection work.Figure 25 indicates tightening work of sleeve-nut with a large screwdriver at the steel anchor. Both ends of ACM brace rod were fixed by four sleeve-nuts as shown in Figure 26 so that the tensile force of 10kN acts in the ACM brace. The shock absorbing rubber shown in Figure 27, which was newly developed by SRI Hybrid Co. Ltd., was used between the fixed anchor and the sleeve-nut.Figure 24. Steel sleeves after Epoxy Figure 25.Tighten work of steel-nut resin injection work with a screwdriverFigure 26. Completion of tightening 27. Rubber ring for shock absorbingdouble Figure steel sleeve nutsFigure 28. Steel sleeve and bracket Figure29. Steel sleeve and bracket afterafter anti-rust painting finishing painting workFigure 30. Completion of ACM brace installationAfter the installation of ACM brace, the steel anchor and sleeve are treated with a tarnish preventive as shown in Figure 28 and 29. Photo 30 indicates the installation completion view of ACM brace fixed on S structure. It is found from this photo that ACM bracing method has a scenic view from the outside of the retrofitted structure because there is not much things to obstruct the view from the inside of the structure.4.Concluding RemarksIn this paper, an advanced seismic retrofitting work for RC and S story building structures built by some old earthquake resistant design codes before 1981 was reported st a large-damaged earthquake. ACM bracing method consists of CFRP rod, steel sleeve, and steel anchor. This ACM bracing method was applied to S two- story building structure in 2010. Materials in the seismic retrofitting work using ACM bracing method and the construction process of ACM brace were described in this paper.The summary obtained in this paper is as follows.(1) ACM brace retrofitting work has several construction advantages such as short construction period and low cost in comparison with the steel bracing method. Namely, ACM bracing method has a high cost performance.(2)Although the installation work of steel braces requires a large construction machine of a crane-currying truck, the installation of ACM brace is not needed any large construction machine and also is effectively conducted under a safe operation.(3) The construction work of ACM brace retrofitting countermeasure does not require a professional engineer or an expert.This ACM bracing method may support a seismic retrofitting politics in the region where has a slightly delay in the seismic countermeasures, and can be a driving force to increase the safety of structures against a large earthquake and changes to a strong region against natural disasters. This kind of seismic retrofitting work for RC and S story building structures will lead to a decrease of earthquake damages in many countries.译文:ACM支撑加固措施在钢结构中的应用摘要一种先进的钢结构抗震改造方法在一片质疑种被提出，该方案采用了AMC（一种先进复合材料）支撑方法。
工程结构中英文对照外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：Structure DesignAbstract: Structure design is the selection of materials and member type ,size, and configuration to carry loads in a safe and serviceable fashion .In general ,structural design implies the engineering of stationary objects such as buildings and bridges ,or objects that maybe mobile but have a rigid shape such as ship hulls and aircraft frames. Devices with parts planned to move with relation to each other(linkages) are generally assigned to the area of mechanical .Key words: Structure Design ；Structural analysis ；structural scheme ；Project requirementsStructural design involved at least five distinct phases of work: project requirements, materials, structural scheme, analysis, and design. For unusual structures or materials a six phase, testing, should be included. These phases do not proceed in a rigid progression , since different materials can be most effective in different schemes , testing can result in change to a design , and a final design is often reached by starting with a rough estimated design , then looping through several cycles of analysis and redesign . Often, several alternative designs will prove quite close in cost, strength, and serviceability. The structural engineer, owner, or end user would then make a selection based on other considerations.Project requirements. Before starting design, the structural engineer must determine the criteria for acceptable performance. The loads or forces to be resisted must be provided. For specialized structures, this may be given directly, as when supporting a known piece of machinery, or a crane of known capacity. For conventional buildings, buildings codes adopted on a municipal, county , or , state level provide minimum design requirements for live loads (occupants and furnishings , snow on roofs , and so on ). The engineer will calculate dead loads(structural and known, permanent installations ) during the design process.For the structural to be serviceable or useful , deflections must also be kept within limits ,since it is possible for safe structural to be uncomfortable “bounce”Very tight deflection limits are set on supports for machinery , since beam sag can cause drive shafts to bend , bearing to burn out , parts to misalign , and overhead cranes to stall . Limitations of sag less than span /1000 ( 1/1000 of the beam length ) are not uncommon . In conventional buildings, beams supporting ceilings often have sag limits of span /360 to avoid plaster cracking, or span /240 to avoid occupant concern (keep visual perception limited ). Beam stiffness also affects floor “bounciness,”which can be annoying if not controlled. In addition , lateral deflection , sway , or drift of tall buildings is often held within approximately height /500 (1/500 of the building height ) to minimize the likelihood of motion discomfort in occupants of upper floors on windy days .Member size limitations often have a major effect on the structural design. For example, a certain type of bridge may be unacceptable because of insufficient under clearance for river traffic, or excessive height endangering aircraft. In building design, ceiling heights and floor-to-floor heights affect the choice of floor framing. Wall thicknesses and column sizes and spacing may also affect theserviceability of various framing schemes.Materials selection. Technological advances have created many novel materials such as carbon fiber and boron fiber-reinforced composites, which have excellent strength, stiffness, and strength-to-weight properties. However, because of the high cost and difficult or unusual fabrication techniques required , they are used only in very limited and specialized applications . Glass-reinforced composites such as fiberglass are more common, but are limited to lightly loaded applications. The main materials used in structural design are more prosaic and include steel, aluminum, reinforced concrete, wood , and masonry .Structural schemes. In an actual structural, various forces are experienced by structural members , including tension , compression , flexure (bending ), shear ,and torsion (twist) . However, the structural scheme selected will influence which of these forces occurs most frequently, and this will influence the process of materials selection.Tension is the most efficient way to resist applied loads ,since the entire member cross section is acting to full capacity and bucking is not a concern . Any tension scheme must also included anchorages for the tension members . In a suspension bridge , for example ,the anchorages are usually massive dead weights at the ends of the main cables . To avoid undesirable changes in geometry under moving or varying loads , tensionschemes also generally require stiffening beams or trusses.Compression is the next most efficient method for carrying loads . The full member cross section is used ,but must be designed to avoid bucking ,either by making the member stocky or by adding supplementary bracing . Domed and arched buildings ,arch bridges and columns in buildings frames are common schemes . Arches create lateral outward thrusts which must be resisted . This can be done by designing appropriate foundations or , where the arch occurs above the roadway or floor line , by using tension members along the roadway to tie the arch ends together ,keeping them from spreading . Compression members weaken drastically when loads are not applied along the member axis , so moving , variable , and unbalanced loads must be carefully considered.Schemes based on flexure are less efficient than tension and compression ,since the flexure or bending is resisted by one side of the member acting in tension while the other side acts in compression . Flexural schemes such as beams , girders , rigid frames , and moment (bending ) connected frames have advantages in requiring no external anchorages or thrust restrains other than normal foundations ,and inherent stiffness and resistance to moving ,variable , and unbalanced loads .Trusses are an interesting hybrid of the above schemes . They are designed to resist loads by spanning in the manner of a flexural member, but act to break up the load into a series of tension and compressionforces which are resisted by individually designed tension and have excellent stiffness and resistance to moving and variable loads . Numerous member-to-member connections, supplementary compression braces ,and a somewhat cluttered appearance are truss disadvantages .Plates and shells include domes ,arched vaults ,saw tooth roofs , hyperbolic paraboloids , and saddle shapes .Such schemes attempt to direct all force along the plane of the surface ,and act largely in shear . While potentially very efficient ,such schemes have very strict limitations on geometry and are poor in resisting point ,moving , and unbalanced loads perpendicular to the surface.Stressed-skin and monologue construction uses the skin between stiffening ribs ,spars ,or columns to resist shear or axial forces . Such design is common in airframes for planes and rockets, and in ship hulls . it has also been used to advantage in buildings. Such a design is practical only when the skin is a logical part of the design and is never to be altered or removed .For bridges , short spans are commonly girders in flexure . As spans increase and girder depth becomes unwieldy , trusses are often used ,as well as cablestayed schemes .Longer spans may use arches where foundation conditions ,under clearance ,or headroom requirements are favorable .The longest spans are handled exclusively by suspension schemes ,since these minimize the crucial dead weight and can be erectedwire by wire .For buildings, short spans are handled by slabs in flexure .As spans increase, beams and girders in flexure are used . Longer spans require trusses ,especially in industrial buildings with possible hung loads . Domes ,arches , and cable-suspended and air –supported roofs can be used over convention halls and arenas to achieve clear areas .Structural analysis . Analysis of structures is required to ensure stability (static equilibrium ) ,find the member forces to be resisted ,and determine deflections . It requires that member configuration , approximate member sizes ,and elastic modulus ; linearity ; and curvature and plane sections . Various methods are used to complete the analysis .Final design .once a structural has been analyzed (by using geometry alone if the analysis is determinate , or geometry plus assumed member sizes and materials if indeterminate ), final design can proceed . Deflections and allowable stresses or ultimate strength must be checked against criteria provided either by the owner or by the governing building codes . Safety at working loads must be calculated . Several methods are available ,and the choice depends on the types of materials that will be used .Pure tension members are checked by dividing load by cross-section area .Local stresses at connections ,such as bolt holes or welds ,require special attention . Where axial tension is combined with bendingmoment ,the sum of stresses is compared to allowance levels . Allowable : stresses in compression members are dependent on the strength of material, elastic modulus ,member slenderness ,and length between bracing points . Stocky members are limited by materials strength ,while slender members are limited by elastic bucking .Design of beams can be checked by comparing a maximum bending stress to an allowable stress , which is generally controlled by the strength of the material, but may be limited if the compression side of the beam is not well braced against bucking .Design of beam-columns ,or compression members with bending moment ,must consider two items . First ,when a member is bowed due to an applied moment ,adding axial compression will cause the bow to increase .In effect ,the axial load has magnified the original moment .Second ,allowable stresses for columns and those for beams are often quite different .Members that are loaded perpendicular to their long axis, such as beams and beam-columns, also must carry shear. Shear stresses will occur in a direction to oppose the applied load and also at right angles to it to tie the various elements of the beam together. They are compared to an allowable shear stress. These procedures can also be used to design trusses, which are assemblies of tension and compression members. Lastly, deflections are checked against the project criteria using finalmember sizes.Once a satisfactory scheme has been analyzed and designed to be within project criteria, the information must be presented for fabrication and construction. This is commonly done through drawings, which indicate all basic dimensions, materials, member sizes, the anticipated loads used in design, and anticipated forces to be carried through connections.结构设计摘要：结构设计是选择材料和构件类型，大小和形状以安全有用的样式承担荷载。
钢结构设计外文翻译参考文献
钢结构设计外文翻译参考文献In the United States。
XXX (ASD)。
Plastic Design (PD)。
and Load and Resistance Factor Design (LRFD)。
In ASD。
stress ns are based on first-order elastic analysis。
XXX。
In PD。
first-order plastic hinge analysis is used in structural analysis。
XXX progressive collapse effects are not included in PD。
they are XXX LRFD。
first-order XXX。
and the XXX。
All three design methods require independent checks。
including K factor ns。
In this paper。
XXX structural system and its components are related。
but the current LRFD n of the American Institute of Steel n (AISC) separates them。
In practical ns。
the XXX in the effective length factor。
This is described in the excerpt from the Technical Memorandum on Social Science Research。
Volume 5.Although the maximum internal forces of the structure and the maximum internal forces of the components are interdependent (but not necessarily coexisting)。
高层结构与钢结构(中英论文翻译用)
高层结构与钢结构(中英论文翻译用) - 建筑技术高层结构与钢结构近年来，尽管一般的建筑结构设计取得了很大的进步，但是取得显著成绩的还要属超高层建筑结构设计。
最初的高层建筑设计是从钢结构的设计开始的。
钢筋混凝土和受力外包钢筒系统运用起来是比较经济的系统，被有效地运用于大批的民用建筑和商业建筑中。
50层到100层的建筑被定义为超高层建筑。
而这种建筑在美国得广泛的应用是由于新的结构系统的发展和创新。
这样的高度需要增大柱和梁的尺寸，这样以来可以使建筑物更加坚固以至于在允许的限度范围内承受风荷载而不产生弯曲和倾斜。
过分的倾斜会导致建筑的隔离构件、顶棚以及其他建筑细部产生循环破坏。
除此之外，过大的摇动也会使建筑的使用者们因感觉到这样的的晃动而产生不舒服的感觉。
无论是钢筋混凝土结构系统还是钢结构系统都充分利用了整个建筑的刚度潜力，因此不能指望利用多余的刚度来限制侧向位移。
在钢结构系统设计中，经济预算是根据每平方英寸地板面积上的钢材的数量确定的。
图示1中的曲线A显示了常规框架的平均单位的重量随着楼层数的增加而增加的情况。
而曲线B显示则显示的是在框架被保护而不受任何侧向荷载的情况下的钢材的平均重量。
上界和下界之间的区域显示的是传统梁柱框架的造价随高度而变化的情况。
而结构工程师改进结构系统的目的就是减少这部分造价。
钢结构中的体系：钢结构的高层建筑的发展是几种结构体系创新的结果。
这些创新的结构已经被广泛地应用于办公大楼和公寓建筑中。
刚性带式桁架的框架结构：为了联系框架结构的外柱和内部带式桁架，可以在建筑物的中间和顶部设置刚性带式桁架。
1974年在米望基建造的威斯康森银行大楼就是一个很好的例子。
框架筒结构：如果所有的构件都用某种方式互相联系在一起，整个建筑就像是从地面发射出的一个空心筒体或是一个刚性盒子一样。
这个时候此高层建筑的整个结构抵抗风荷载的所有强度和刚度将达到最大的效率。
这种特殊的结构体系首次被芝加哥的43层钢筋混凝土的德威特红棕色的公寓大楼所采用。
关于钢结构的英文作文
关于钢结构的英文作文英文：Steel structure is a popular choice for building construction due to its many advantages. Firstly, it is durable and can withstand harsh weather conditions and natural disasters such as earthquakes and hurricanes. This is because steel is a strong and flexible material that can absorb shock and resist deformation. Secondly, steel structures are easy to assemble and disassemble, making them ideal for temporary or mobile buildings such as exhibition halls or warehouses. Thirdly, steel is a sustainable material that can be recycled and reused, reducing waste and environmental impact.In addition, steel structures offer design flexibility and can be customized to meet specific requirements. For example, the shape and size of the structure can be adjusted to fit the available space and the intended use of the building. Moreover, steel structures can be combinedwith other materials such as glass, wood or concrete to create a unique and aesthetically pleasing design.However, there are also some challenges associated with steel structure construction. One of the main challenges is corrosion, which can weaken the structure over time. This can be prevented by applying protective coatings or using stainless steel. Another challenge is the cost, as steel structures can be more expensive than traditional building materials such as wood or brick. However, the long-term benefits of durability and sustainability may outweigh the initial cost.Overall, steel structure construction offers many advantages and is a viable option for building projects of various sizes and purposes.中文：钢结构是建筑施工中一个受欢迎的选择，因为它有许多优点。
应用钢结构设计外文翻译
Applied Structural Steel Design (4th Edition)by George F. Spiegel and George F. Limbrunner9-2Open Web Steel Joists, K-SeriesThe design of the K-Series joist chord is based on a steel minimum yield strength of 50,000 psi. The design of the web members may be based on a steel minimum yield strength of 36,000 psi or 50,000 psi.An example of the standard designation for K-Series joists is 22K7. The depth of this joist is 22 in. K represents the series, and the number 7 denotes the relative size of the chords of the joist. Chord sizes are designated by the numbers 3 through 12, the size increasing with increasing number. The chord and web members may vary in shape and makeup from manufacturer to manufacturer, but the design and the capacity of the joists must conform to the SJI specifications and to the standardized load tables. The K-Series standard load table and the economy table (which is used for selection) are applicable where the joists are installed up to a maximum slope of 2 in. per foot.The use of open web steel joists in any given application must be based on SJI requirements as furnished in its standard specifications. These requirements for the K-Series joists are summarized as follows:In construction that uses joists, bridging and bridging anchors are required for the primary purpose of furnishing lateral stability for the joists, particularly during the construction phase. The bridging spans between and perpendicular to the steel joists.It is required that one end of all joists be attached to their supports before allowing the weight of an erector on the joists. When bolted connections are used, the bolts must be snug tightened. All bridging must be completely installed and the joists permanently fastened into place before the application of any construction loads. Even under the weight of an erector, the joists may exhibit some degree of lateral instability until the bridging is installed. The bridging also serves the purpose of holding the steel joists in position as shown on the plans. The minimum number of rows of bridging is a function of the joist chord size and span length. A table is furnished in the standard specifications that establishes the required number of rows of bridging. Spacing of bridging rows should be approximately equal. Two permissible types of bridging may be observed in Figure 9-2. Horizontal bridging (Figure 9-2a) consists of two continuous horizontal steel members, one attached to the top chord and the other attached to the bottom chord by means of welding or mechanical fasteners. The attachment must be capable of resisting a horizontal force of not less than 700 lb. If the bridging member is a round bar, the diameter must be at least 2 in. The maximum slenderness ratia4V/rj~of-the bridging member cannot exceed 300, where k is the distance between bridging attachments and r is the least radius of gyration of the bridging member. The bridging member shall be designed for a compressive force of 0.24 times the area of the top chord. Diagonal bridging (Figure 9-2b) consists of cross-bracing with a maximum B/r of 200, with Z and r as defined previously. Where the cross-bracing members connect at their intersection, E is the distance between the intersection attachment and chord attachment. The ends of all bridginglines terminating at walls or beams must be properly anchored. A typical detail may be observed in Figure 9-2b.FIGURE 9-2 Typical bridging.Joist extensions are frequently used with K-Series joists to support a variety of over-hang conditions. Two types are shown in Figure 9-3c and d. The first is the Top Chord Extension (S Type), which has only the top chord angles extended. The second is the Extended End (R Type), in which the standard 2 and 1/2-in. end bearing depth is maintained over the entire length of the extension. The R Ty pe (reinforced) involves reinforcing the top chord. The S Type (simple) is more economical and should be specified whenever possible.Load tables for K-Series Top Chord Extension and Extended finds axe furnished by the SJI. Specific designs and load tables, however, are generally furnished by the various joist manufacturers and can be used to advantage.Ceiling extensions (Figure 9-3b) in the form of an extended bottom chord element or a loose unit, whichever is standard with the joist manufacturer, are frequently used to support ceilings that are to be attached directly to the bottom of the joists. They are not furnished for the support of suspended ceilings.FIGURE 9-3 Typical joist detailsWhen joists are used in conjunction with a corrugated metal deck and concrete slab, the cast-in-place slab should not be less than 2 in. thick.The typical standard K-Series joist is designed for a simple span subjected to uniformly distributed load for its full span length, resulting in a linear shear distribution (maximum at the supports and zero at midspan) and a parabolic moment distribution (zero at the supports and maximum at midspan). The KCS joist is a new type of K-Series joist developed to overcome some of the limitations of the standard K-Series joist. The KCS joist may be used for special design applications requiring a joist capable of supporting nonuniform loads, concentrated loads, or combinations thereof in addition to or independent of the normal uniform load.The KCS joists are designed in accordance with the SJI Standard Specifications for K-Series joists and range in depth from 10 in. to 30 in. Load tables furnished by the SJI provide the shear and moment capacity of each joist. The designer must calculate the maximum moment and shear imposed and then select the appropriate KCS joist.9-3Floor VibrationsEven when the structural design of the steel joists is accomplished in accordance with design specifications, a floor system may be susceptible to undesirable vibrations. This phenomenon isseparate and different from strength and has to do mainly with the psychological and physiologicalresponse of humans to motion. Large open floor areas without floor-to-ceiling partitions may be subject to such undesirable vibrations.The ASDS Commentary recommends a minimum depth-to-span ratio of 1/20 for a steel beam supporting a large open floor area free of partitions. In addition, the SJI requires a minimum depth-to-span ratio of 1/24 for steel joists, although a generally accepted practice for steel joist roofs and floors is to use a minimum depth-to-span ratio of 1/20. Even if these recommendations and requirements are satisfied, a vibration analysis should be made, particularly when a floor system is composed of steel joists that support a thin-concrete slab placed on steel metal deck. References 2 and 3 contain relatively brief and sufficiently accurate methods that can be used to determine (1) whether disturbing vibrations will be present in a floor system and (2) possible design solutions for the problem. Reference 4 contains insight on vibrations in steel framed floors.应用钢结构设计（第4版）by George F. Spiegel and George F. Limbrunner9-2空腹钢搁栅，K系列K系列搁栅弦的设计是基于钢弦的最小屈服强度为50000psi。
钢结构建造的特点英文作文
Characteristics of Steel Structure ConstructionSteel structure construction has revolutionized modern architecture with its distinct features that offer flexibility, strength, and sustainability. From towering skyscrapers to expansive industrial complexes, steel structures have become synonymous with efficiency and innovation in the construction industry.Strength and DurabilityOne of the hallmark features of steel structure construction is its exceptional strength-to-weight ratio. Steel’s inherent properties allow for the creation of robust frameworks capable of supporting heavy loads over long spans without compromising structural integrity. This strength is particularly advantageous in seismic zones where buildings must withstand significant lateral forces. Design Flexibility and AdaptabilitySteel structures offer unparalleled design flexibility, enabling architects and engineers to create striking and complex shapes that would be challenging with traditional building materials. This adaptability allows for large open spaces, minimal column interference, and innovative architectural forms that define modern urban landscapes.Construction EfficiencyThe prefabrication and assembly of steel components off-site streamline the construction process, reducing on-site labor requirements and accelerating project timelines. This efficiency not only minimizes construction costs but also enhances safety by minimizing exposure to on-site hazards and adverse weather conditions.Environmental SustainabilitySteel is a highly sustainable building material due to its recyclability and efficient use of resources. Recycled steel retains its structural integrity, reducing the demand for raw materials and lowering carbon emissions associated with manufacturing new steel products. Additionally, steel structures can be dismantled and repurposed, further extending their lifecycle and minimizing construction waste.Cost-effectivenessWhile initial costs may be higher than traditional building materials, the long-term benefits of steel structure construction often outweigh these expenses. Reduced maintenance requirements, extended durability, and faster construction times translate into significant cost savings over the lifespan of the building.ConclusionIn conclusion, steel structure construction stands as a testament to innovation in the architectural and engineering fields, offering unparalleled strength, design flexibility, and sustainability. As urbanization and the demand for efficient, resilient buildings continue to grow, steel structures will play a pivotal role in shaping the skylines of cities worldwide, embodying both the artistry and practicality of modern construction techniques.。
钢结构稳定设计论文
浅析钢结构稳定设计简介：钢结构的稳定性能是决定其承载力的一个重要因素，因此论文对钢结构稳定设计提出了在设计过程中设计人员应该明确知道的一些基本概念，以便帮助设计人员在设计中树立正确而完整的稳定分析和稳定设计的理念；随着新型结构不断地出现，在应用过程中，对其性能不够了解、设计经验有缺陷，导致发生失稳事故，因此论文介绍了钢结构设计中可能遇到的稳定问题，以便设计人员在钢结构设计过程中参考。
关键字：钢结构结构稳定失稳结构设计introduction: the steel structure of the performance is stable to determine the bearing capacity of the one of the important factors, so papers on steel structure stability design and puts forward in the design process design personnel should be clearly know some basic concepts, to help designers in the design to set up correct and complete stability analysis and stability design idea; with the new structure keep popping up, in the application process, its performance don’t know enough about, design experience with a defect, causing instability accident, so this paper introduces steel structure design may be met in stability issues, so as to design personnel in the steel structure design process reference.key word: steel structure stability instability structure design中图分类号：tu391文献标识码：a 文章编号：1、引言钢结构的稳定问题普遍存在于钢结构设计中，凡是结构的受压部位，在设计时都必须认真考虑其稳定性。
钢结构设计中稳定性分析论文
钢结构设计中稳定性分析探讨摘要：钢结构是用钢材经过加工、连接、安装而建成的一种工程结构，它需要承受各种可能的自然环境和人为环境作用，并应满足各种预定功能要求和具有足够的可靠性及良好的社会经济效益。
在钢结构设计中，稳定是较为重要的一个环节，本文分析了钢结构稳定设计应遵循的原则以及钢结构稳定设计特点，并提出钢结构稳定性设计的计算方法。
关键词：钢结构设计稳定性1 钢结构稳定设计存在问题分析（1）强度与稳定的区别。
强度问题是指结构或者单个构件在稳定平衡状态下由荷载所引起地最大应力(或内力)是否超过建筑材料的极限强度，因此是一个应力问题。
极限强度的取值取决于材料的特性。
对混凝土等脆性材料，可取它的最大强度，对钢材则常取它的屈服点。
稳定问题则与强度问题不同，它主要是找出外荷载与结构内部抵抗力间的不稳定平衡状态，即变形开始急剧增长的状态。
从而设法避免进入该状态，因此，它是一个变形问题。
如轴压柱，由于失稳，侧向挠度使柱中增加数量很大的弯矩，因而柱子的破坏荷载可以远远低于它的轴压强度。
显然，轴压强度不是柱子破坏的主要原因。
（2）目前在网壳结构稳定性的研究中，梁一柱单元理论已成为主要的研究工具。
但梁一柱单元是否能真实反映网壳结构的受力状态还很难说，虽然有学者对梁一柱单元进行过修正，主要问题在于如何反映轴力和弯矩的耦合效应。
（3）在大跨度结构设计中整体稳定与局部稳定的相互关系也是一个值得探讨的问题。
目前大跨度结构设计中取一个统一的稳定安全系数，未反映整体稳定与局部稳定的关联性。
（4）预张拉结构体系的稳定设计理论还很不完善。
目前还没有一个完整合理的理论体系来分析预张拉结构体系的稳定性。
（5）钢结构体系的稳定性研究中存在许多随机因素的影响。
目前结构随机影响分析所处理的问题大部分局限于确定的结构参数、随机荷载输入这样一个格局范围，而在实际工程中，由于结构参数的不确定性，会引起结构响应的显著差异。
所以应着眼于考虑随机参数的结构极值失稳、干扰型屈曲、跳跃型失稳问题的研究。
钢结构稳定设计指南内容简介
钢结构稳定设计指南内容简介## Guide to Stability Design of Steel Structures.This guide provides comprehensive guidance on the stability design of steel structures, covering various aspects such as:General principles of stability.Classification of stability problems.Methods of analysis.Design criteria.Connection design.Construction and fabrication considerations.The guide is intended to assist engineers in ensuringthe stability of steel structures under various loading conditions, including:Gravity loads.Lateral loads (wind, earthquake)。
Thermal loads.The topics covered in this guide include:Introduction to stability design.Elastic buckling theory.Inelastic buckling theory.Plate buckling.Shell buckling.Lateral-torsional buckling.Connection design for stability.Construction and fabrication considerations.## 钢结构稳定设计指南内容简介。
毕业设计论文外文文献翻译中英文对照工程类高层结构与钢结构
毕业设计论文外文文献翻译中英文对照工程类高层结构与钢结构高层结构是城市发展的重要组成部分，其对城市景观和功能起着重要的影响。
钢结构是高层建筑中常用的结构形式之一，它具有重量轻、强度高、施工速度快等优点，被广泛应用于高层建筑的梁、柱、框架等部位。
本文将重点介绍高层结构和钢结构之间的关系，以及如何合理应用钢结构来提高高层建筑的性能和经济效益。
钢结构的应用能够有效地提高高层建筑的稳定性和抗震性能。
高层建筑由于其自身的高度和自重，容易产生较大的荷载，对结构的稳定性提出了较高的要求。
钢结构具有良好的刚性和接头性能，能够有效地承受和分散这些荷载，提供稳定的结构支撑。
此外，钢结构还具有较好的抗震性能，可以有效地减轻震动对建筑物的损坏和破坏。
钢结构可以提供较大的建筑自由度和灵活性，满足高层建筑多样化的功能需求。
高层建筑通常具有多功能、复合型的特征，需要满足不同的使用要求。
钢结构具有较高的强度和刚度，可以支撑大跨度的空间，满足大空间内部的活动和使用需求。
此外，钢结构还可以采用预制的方式进行制造和安装，提供更多灵活的设计选择和改变，以满足建筑功能的变化和扩展。
钢结构的施工速度快，可有效缩短工期，提高项目的经济效益。
高层建筑的施工周期通常较长，会导致项目成本的增加和利润的减少。
而钢结构的制造和安装过程较为简单，可以实现快速装配和安装，从而能够大大缩短高层建筑的施工周期。
此外，钢结构材料的可回收利用性较高，可以降低建筑废弃物的产生，减少对环境的影响，提高项目的可持续性。
综上所述，高层结构与钢结构之间存在着密切的关系。
钢结构的应用能够提高高层建筑的稳定性、抗震性能，同时可以满足多功能和复合型的建筑需求，并且可以提高施工速度，提高项目的经济效益。
因此，在高层建筑的设计和施工中，合理应用钢结构将会发挥重要的作用，为城市的发展和建设做出贡献。
High-rise Structures and Steel StructuresThe application of steel structures can effectively improve the stability and seismic performance of high-rise buildings. Due to the height and self-weight of high-rise buildings, they are prone to generate significant loads, which pose higher requirements for structural stability. Steel structures have excellent rigidity and joint performance, allowing them to bear and distribute these loads effectively, providing stable structural support. Additionally, steel structures have good seismic performance, effectively reducing damage and destruction caused by vibrations to the buildings.The fast construction speed of steel structures can effectively shorten the project duration, enhancing the economic benefits of projects. The construction period of high-rise buildings is typically long, leading to increased project costs and reduced profits. However, the manufacturing and installation processes of steel structures are relatively simple, enabling rapid assembly and installation, thus significantly reducing the construction period of high-rise buildings. Additionally, steelstructure materials have high recyclability, reducing the production of construction waste, minimizing environmental impact, and improving project sustainability.。
建筑钢结构论文：浅谈钢结构稳定性的设计
建筑钢结构论文：浅谈钢结构稳定性的设计在现代建筑领域中，钢结构凭借其高强度、大跨度、施工快捷等诸多优势，得到了广泛的应用。
然而，钢结构的稳定性设计是确保其安全可靠的关键环节。
钢结构的稳定性一旦出现问题，可能会导致严重的结构破坏甚至坍塌事故，给生命财产带来巨大损失。
因此，深入探讨钢结构稳定性的设计具有重要的现实意义。
钢结构稳定性问题的本质是结构在受到外部荷载作用时，能否保持其原有平衡状态而不发生失稳破坏。
钢结构的失稳形式多种多样，常见的有弯曲失稳、扭转失稳和弯扭失稳等。
弯曲失稳通常发生在受压的梁柱构件中，当压力超过一定限度时，构件会突然发生弯曲变形而丧失承载能力。
扭转失稳则多见于受扭的构件，如钢梁的扭转。
弯扭失稳则是弯曲和扭转共同作用下导致的失稳现象，常见于一些复杂的结构构件。
在钢结构稳定性设计中，首先要准确分析和计算结构所承受的荷载。
荷载包括恒载、活载、风载、地震作用等。
这些荷载的大小、分布和组合方式对结构的稳定性有着直接的影响。
例如，在风荷载较大的地区，设计时必须充分考虑风对钢结构的作用，确保结构在风荷载下不会发生失稳。
材料的性能也是影响钢结构稳定性的重要因素。
钢材的强度、弹性模量、屈服点等性能指标直接关系到结构的承载能力和稳定性。
不同的钢材品种和规格具有不同的性能，因此在设计时需要根据具体情况选择合适的钢材。
同时，还要考虑钢材在长期使用过程中的性能变化，如钢材的锈蚀、疲劳等对结构稳定性的影响。
钢结构的几何形状和尺寸对其稳定性也有着至关重要的作用。
构件的长细比是衡量其稳定性的一个重要参数。
长细比越大，构件越容易发生失稳。
因此，在设计时要合理控制构件的长细比，通过增加截面尺寸、设置支撑等方式来提高构件的稳定性。
此外，节点的设计也不容忽视。
节点的连接方式和刚度会影响结构的整体稳定性，不合理的节点设计可能导致局部失稳，进而影响整个结构的稳定性。
在计算钢结构的稳定性时，需要运用适当的理论和方法。
目前常用的有经典的欧拉理论、切线模量理论等。
钢结构的英文作文
钢结构的英文作文下载温馨提示:该文档是我店铺精心编制而成，希望大家下载以后，能够帮助大家解决实际的问题。
文档下载后可定制随意修改，请根据实际需要进行相应的调整和使用，谢谢!并且，本店铺为大家提供各种各样类型的实用资料，如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等，如想了解不同资料格式和写法，敬请关注!Download tips: This document is carefully compiled by theeditor. I hope that after you download them,they can help yousolve practical problems. The document can be customized andmodified after downloading,please adjust and use it according toactual needs, thank you!In addition, our shop provides you with various types ofpractical materials,such as educational essays, diaryappreciation,sentence excerpts,ancient poems,classic articles,topic composition,work summary,word parsing,copyexcerpts,other materials and so on,want to know different data formats andwriting methods,please pay attention!Steel structures are really strong. They can hold up a lot of weight and are very durable.Using steel in construction is a great choice. It's easy to work with and can be shaped into different forms.Steel is also resistant to fire and other disasters. It provides a high level of safety.Many modern buildings use steel structures. They look really cool and give a unique appearance.The strength of steel allows for more creative designs in architecture. It's amazing what can be done with it.。
结构稳定论文之钢结构设计(英文版)
Graduate Course Work Steel Structure Stability DesignAbstractSteel structure has advantages of light weight, high strength and high degree of industryali zation, which has been widely used in the construction engineering. We often hear this the accident case caused by its instability and failure of structure of casualties and property losses, and the cause of the failure is usually caused by structure design flaws. This paper says the experiences in the design of stability of steel structure through the summary of the stability of steel structure design of the concept, principle, analysis method and combination with engineering practice.Key words:steel structure; stability design; detail structureSteel Structure Stability DesignStructurally stable systems were introduced by Aleksandr Andronov and Lev Pontryagin in 1937 under the name "systèmes grossières", or rough systems. They announced a characterization of rough systems in the plane, the Andronov–Pontryagin criterion. In this case, structurally stable systems are typical, they form an open dense set in the space of all systems endowed with appropriate topology. In higher dimensions, this is no longer true, indicating that typical dynamics can be very complex (cf strange attractor). An important class of structurally stable systems in arbitrary dimensions is given by Anosov diffeomorphisms and flows.In mathematics, structural stability is a fundamental property of a dynamical system which means that the qualitative behavior of the trajectories is unaffected by C1-small perturbations. Examples of such qualitative properties are numbers of fixed points and periodic orbits (but not their periods). Unlike Lyapunov stability, which considers perturbations of initial conditions for a fixed system, structural stability deals with perturbations of the system itself. Variants of this notion apply to systems of ordinary differential equations, vector fields on smooth manifolds and flows generated by them, and diffeomorphisms.The stability is one of the content which needs to be addressed in the design of steel structure engineering. Three are more engineering accident case due to the steel structure instability in the real life. For example,the stadium, in the city of Hartford 92 m by 110 m to the plane of space truss structure, suddenly fell on the ground in 1978. The reason is the compressive bar buckling instability;13.2 m by 18.0 m steel truss, in 1988,lack of stability of the web member collapsed in construction process in China;On January 3, 2010 in the afternoon, 38 m steel structure bridge in Kunming New across suddenly collapsed, killing seven people, 8 people seriously injured, 26 people slightly injured.The reason is that the bridge steel structure supporting system is out of stability, suddenly a bridge collapsing down to 8 m tall. We can see from the above case, the usual cause of instability and failure of steel structure is the unreasonable structural design, structural design defects.To fundamentally prevent such accidents, stability of steel structure design is the key.Structural stability of the system provides a justification for applying the qualitative theory of dynamical systems to analysis of concrete physical systems. The idea of such qualitative analysisgoes back to the work of Henri Poincaré on the three-body problem in celestial mechanics. Around the same time, Aleksandr Lyapunov rigorously investigated stability of small perturbations of an individual system. In practice, the evolution law of the system (i.e. the differential equations) is never known exactly, due to the presence of various small interactions. It is, therefore, crucial to know that basic features of the dynamics are the same for any small perturbation of the "model" system, whose evolution is governed by a certain known physical law. Qualitative analysis was further developed by George Birkhoff in the 1920s, but was first formalized with introduction of the concept of rough system by Andronov and Pontryagin in 1937. This was immediately applied to analysis of physical systems with oscillations by Andronov, Witt, and Khaikin. The term "structural stability" is due to Solomon Lefschetz, who oversaw translation of their monograph into English. Ideas of structural stability were taken up by Stephen Smale and his school in the 1960s in the context of hyperbolic dynamics. Earlier, Marston Morse and Hassler Whitney initiated and René Thom developed a parallel theory of stability for differentiable maps, which forms a key part of singularity theory. Thom envisaged applications of this theory to biological systems. Both Smale and Thom worked in direct contact with Maurício Peixoto, who developed Peixoto's theorem in the late 1950's.When Smale started to develop the theory of hyperbolic dynamical systems, he hoped that structurally stable systems would be "typical". This would have been consistent with the situation in low dimensions: dimension two for flows and dimension one for diffeomorphisms. However, he soon found examples of vector fields on higher-dimensional manifolds that cannot be made structurally stable by an arbitrarily small perturbation (such examples have been later constructed on manifolds of dimension three). This means that in higher dimensions, structurally stable systems are not dense. In addition, a structurally stable system may have transversal homoclinic trajectories of hyperbolic saddle closed orbits and infinitely many periodic orbits, even though the phase space is compact. The closest higher-dimensional analogue of structurally stable systems considered by Andronov and Pontryagin is given by the Morse–Smale systems.Structure theory of stability study was conducted on the mathematical model of the ideal, and the actual structure is not as ideal as mathematical model, in fact ,we need to consider the influence of various factors. For example ,for the compressive rods, load could not have absolute alignment section center; There will always be some initial bending bar itself, the so-called"geometric defects"; Material itself inevitably has some kind of "defect", such as the discreteness of yield stress and bar manufacturing methods caused by the residual stress, etc. So, in addition to the modulus of elasticity and geometry size of bar, all the above-mentioned factors affecting the bearing capacity of the push rod in different degrees, in the structure design of this influence often should be considered. Usually will be based on the ideal mathematical model to study the stability of the theory is called buckling theory, based on the actual bar study consider the various factors related to the stability of the stability of the ultimate bearing capacity theory called the theory ofcrushing.Practical bar, component or structure damage occurred during use or as the loading test of the buckling load is called crushing load and ultimate bearing capacity. For simplicity, commonly used buckling load. About geometric defects, according to a large number of experimental results, it is generally believed to assume a meniscus curve and its vector degrees for the rod length of 1/1000. About tissue defects, in the national standard formula is not the same, allow the buckling stress curve given by the very different also, some problems remain to be further research.1.Steel structure stability design concept1.1.The difference between intensity and stabilityThe intensity refers to that the structure or a single component maximum stress (or internal force)caused by load in stable equilibrium state is more than the ultimate strength of building materials, so it is a question of the stress. The ultimate strength value is different according to the characteristics of the material varies. for steel ,it is the yield point. The research of stability is mainly is to find the external load and structure unstable equilibrium between internal resistance. That is to say, deformation began to rapid growth and we should try to avoid the structure entering the state, so it is a question of deformation. For example, for an axial compression columns, in the condition column instability, the lateral deflection of the column add a lot of additional bending moment, thus the fracture load of pillars can be far less than its axial compression strength. At this point, the instability is the main reason of the pillar fracture .1.2.The classification of the steel structure instability1)The stability problem with the equilibrium bifurcation(Branch point instability).2)The axial compression buckling of the perfect straight rod and tablet compression bucklingall belong to this category.3)The stability of the equilibrium bifurcation problem(Extreme value point instability).4)The ability of the loss of stability of eccentric compression member made of constructionsteel in plastic development to a certain degree , fall into this category.5)Jumping instability6)Jumping instability is a kind of different from the above two types of stability problem. Itis a jump to another stable equilibrium state after loss of stability balance.2.The principle of steel structure stability design2.1.For the steel structure arrangement, the whole system and the stability of the part requirements must be considered ,and most of the current steel structure is designed according to plane system, such as truss and frame. The overall layout of structure can guarantee that the flat structure does not appear out-of-plane instability,such as increasing the necessary supporting artifacts, etc. A planar structures of plane stability calculation is consistent with the structure arrangement.2.2.Structure calculation diagram should be consistent with a diagram of a practical calculation method is based on. When designing a single layer or multilayer frame structure, we usually do not make analysis of the framework stability but the frame column stability calculation. When we use this method to calculate the column frame column stability , the length factor should be concluded through the framework of the overall stability analysis which results in the equivalent between frame column stability calculation and stability calculation. For a single layer or multilayer framework, the column length coefficient of computation presented by Specification for design of steel structures (GB50017-2003) base on five basic assumptions. Including:all the pillars in the framework is the loss of stability at the same time, that is ,the critical load of the column reach at the same time. According to this assumes, each column stability parameters of the frame and bar stability calculation method, is based on some simplified assumptions or typical.Designers need to make sure that the design of structure must be in accordance with these assumptions.2.3.The detail structure design of steel structure and the stable calculation of component should be consistent. The guarantee that the steel structure detail structure design and component conforms to the stability of the calculation is a problem that needs high attention in the design of steel structure.Bending moment tonon-transmission bending moment node connection should be assigned to their enough rigidity and the flexibility.Truss node should minimize the rods' bias.But, when it comes to stability, a structure often have different in strength or special consideration. But requirement above in solving the beam overall stability is not enough.Bearing need to stop beam around the longitudinal axis to reverse,meanwhile allowing the beam in the in-plane rotation and free warp beam end section to conform to the stability analysis of boundary conditions. 3.The analysis method of the steel structure stabilitySteel structure stability analysis is directed at the outer loads under conditions of the deformation of structure.The deformation should be relative to unstability deformation of the structure or buckling. Deformation between load and structure is nonlinear relationship , which belongs to nonlinear geometric stability calculation and uses a second order analysis method. Stability calculated, both buckling load and ultimate load, can be regarded as the calculation of the stability bearing capacity of the structure or component.In the elastic stability theory, the calculation method of critical force can be mainly divided into two kinds of static method and energy method.3.1.Static methodStatic method, both buckling load and ultimate load, can be regarded as the calculation of the stability bearing capacity of the structure or component. Follow the basic assumptions in establishing balance differential equation:1)Components such as cross section is a straight rod.2)Pressure function is always along the original axis component3)Material is in accordance with hooke's law, namely the linear relationship between thestress and strain.4)Component accords with flat section assumption, namely the component deformation infront of the flat cross-section is still flat section after deformation.5)Component of the bending deformation is small ant the curvature can be approximatelyrepresented by the second derivative of the deflection function.Based on the above assumptions, we can balance differential equation,substitude into the corresponding boundary conditions and solve both ends hinged the critical load of axial compression component .3.2.Energy methodEnergy method is an approximate method for solving stability bearing capacity, through the principle of conservation of energy and potential energy in principle to solve the critical load values.1)The principle of conservation of energy to solve the critical loadWhen conservative system is in equilibrium state, the strain energy storaged in the structure is equal to the work that the external force do, namely, the principle of conservation of energy. As the critical state of energy relations:ΔU =ΔWΔU—The increment of strain energyΔW—The increment of work forceBalance differential equation can be established by the principle of conservation of energy.2)The principle of potential energy in value to solve the critical load valueThe principle of potential energy in value refers to: For the structure by external force, when there are small displacement but the total potential energy remains unchanged,that is, the total potential energy with in value, the structure is in a state of balance. The expression is:dΠ=dU-dW =0dU—The change of the structure strain energy caused by virtual displacement , it is always positive;dW—The work the external force do on the virtual displacement;3.3.Power dynamics methodMany parts of the qualitative theory of differential equations and dynamical systems deal with asymptotic properties of solutions and the trajectories—what happens with the system after a long period of time. The simplest kind of behavior is exhibited by equilibrium points, or fixed points, and by periodic orbits. If a particular orbit is well understood, it is natural to ask next whether asmall change in the initial condition will lead to similar behavior. Stability theory addresses the following questions: will a nearby orbit indefinitely stay close to a given orbit? will it converge to the given orbit (this is a stronger property)? In the former case, the orbit is called stable and in the latter case, asymptotically stable, or attracting. Stability means that the trajectories do not change too much under small perturbations. The opposite situation, where a nearby orbit is getting repelled from the given orbit, is also of interest. In general, perturbing the initial state in some directions results in the trajectory asymptotically approaching the given one and in other directions to the trajectory getting away from it. There may also be directions for which the behavior of the perturbed orbit is more complicated (neither converging nor escaping completely), and then stability theory does not give sufficient information about the dynamics.One of the key ideas in stability theory is that the qualitative behavior of an orbit under perturbations can be analyzed using the linearization of the system near the orbit. In particular, at each equilibrium of a smooth dynamical system with an n-dimensional phase space, there is a certain n×n matrix A whose eigenvalues characterize the behavior of the nearby points (Hartman-Grobman theorem). More precisely, if all eigenvalues are negative real numbers or complex numbers with negative real parts then the point is a stable attracting fixed point, and the nearby points converge to it at an exponential rate, cf Lyapunov stability and exponential stability. If none of the eigenvalues is purely imaginary (or zero) then the attracting and repelling directions are related to the eigenspaces of the matrix A with eigenvalues whose real part is negative and, respectively, positive. Analogous statements are known for perturbations of more complicated orbits.For the structure system in balance,if making it vibrate by applying small interference vibration,the structure of the deformation and vibration acceleration is relation to the structure load. When the load is less than the limit load of a stable value, the acceleration and deformation is in the opposite direction, so the interference is removed, the sports tend to be static and the structure of the equilibrium state is stable; When the load is greater than the ultimate load of stability, the acceleration and deformation is in the same direction, even to remove interference, movement are still divergent, therefore the structure of the equilibrium state is unstable. The critical state load is the buckling load of the structure,which can be made of the conditions that the structure vibrationfrequency is zero solution.At present, a lot of steel structure design with the aid of computer software for structural steel structure stress calculation, structure and component within the plane of strength and the overall stability calculation program automatically, can be counted on the structure and component of the out-of-plane strength and stability calculation, designers need to do another analysis, calculation and design. At this time the entire structure can be in the form of elevation is decomposed into a number of different layout structure, under different levels of load, the structure strength and stability calculation.local stability after buckling strength of the beam, it can be set up to the beam transverse or longitudinal stiffener, in order to solve the problem, the local stability of the beam stiffening rib according to Specification for Design of Steel Structures (GB50017-2003) ; Finite element analysis for a web after buckling strength calculation according to specification for design of steel structures (GB50017-2003) 4, 4 provisions. Axial compression member and a local bending component has two ways: one is the control board free overhanging flange width and thickness ratio of; The second is to control web computing the ratio of the height and thickness. For circular tube section compression member, should control the ratio of outer diameter and wall thickness and stiffener according to specification for design of steel structures (GB50017-2003), 5 4 rule.4.ConclusionSteel structure has advantages of light weight, high strength and high degree of industrialization and has been widely used in the construction engineering.I believe that through to strengthen the overall stability and local stability of the structure and the design of out-of-plane stability, we could overcome structure design flaws and its application field will be more and more widely.referencesGB50017-2003,Design Code for Steel Structures[S]Chen Shaofan, Steel structure design principle [M]. Beijing: China building industry press, 2004 Kalman R.E. & Bertram J.F: Control System Analysis and Design via the Second Method of Lyapunov, J. Basic Engrg vol.88 1960 pp.371; 394LaSalle J.P. & Lefschetz S: Stability by Lyapunov's Second Method with Applications, New York 1961 (Academic)Smith M.J. and Wisten M.B., A continuous day-to-day traffic assignment model and the existence of a continuous dynamic user equilibrium , Annals of Operations Research, V olume 60, 1995 Arnold, V. I. (1988). Geometric methods in the theory of differential equations. Grundlehren der Mathematischen Wissenschaften, 250. Springer-Verlag, New York. ISBN 0-387-96649-8 Structural stability at Scholarpedia, curated by Charles Pugh and Maurício Matos Peixoto.9。
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Graduate Course Work Steel Structure Stability DesignSchool: China University of MiningName: Liu FeiStudent ID: TSP130604088Grade: 2013Finish Date: 2014.1.1AbstractSteel structure has advantages of light weight, high strength and high degree of industryali zation, which has been widely used in the construction engineering. We often hear this the accident case caused by its instability and failure of structure of casualties and property losses, and the cause of the failure is usually caused by structure design flaws. This paper says the experiences in the design of stability of steel structure through the summary of the stability of steel structure design of the concept, principle, analysis method and combination with engineering practice.Key words:steel structure; stability design; detail structureSteel Structure Stability DesignStructurally stable systems were introduced by Aleksandr Andronov and Lev Pontryagin in 1937 under the name "systèmes grossières", or rough systems. They announced a characterization of rough systems in the plane, the Andronov–Pontryagin criterion. In this case, structurally stable systems are typical, they form an open dense set in the space of all systems endowed with appropriate topology. In higher dimensions, this is no longer true, indicating that typical dynamics can be very complex (cf strange attractor). An important class of structurally stable systems in arbitrary dimensions is given by Anosov diffeomorphisms and flows.In mathematics, structural stability is a fundamental property of a dynamical system which means that the qualitative behavior of the trajectories is unaffected by C1-small perturbations. Examples of such qualitative properties are numbers of fixed points and periodic orbits (but not their periods). Unlike Lyapunov stability, which considers perturbations of initial conditions for a fixed system, structural stability deals with perturbations of the system itself. Variants of this notion apply to systems of ordinary differential equations, vector fields on smooth manifolds and flows generated by them, and diffeomorphisms.The stability is one of the content which needs to be addressed in the design of steel structure engineering. Three are more engineering accident case due to the steel structure instability in the real life. For example,the stadium, in the city of Hartford 92 m by 110 m to the plane of space truss structure, suddenly fell on the ground in 1978. The reason is the compressive bar buckling instability;13.2 m by 18.0 m steel truss, in 1988,lack of stability of the web member collapsed in construction process in China;On January 3, 2010 in the afternoon, 38 m steel structure bridge in Kunming New across suddenly collapsed, killing seven people, 8 people seriously injured, 26 people slightly injured.The reason is that the bridge steel structure supporting system is out of stability, suddenly a bridge collapsing down to 8 m tall. We can see from the above case, the usual cause of instability and failure of steel structure is the unreasonable structural design, structural design defects.To fundamentally prevent such accidents, stability of steel structure design is the key.Structural stability of the system provides a justification for applying the qualitative theory of dynamical systems to analysis of concrete physical systems. The idea of such qualitative analysis goes back to the work of Henri Poincaré on the three-body problem in celestial mechanics. Around the same time, Aleksandr Lyapunov rigorously investigated stability of small perturbations of an individual system. In practice, the evolution law of the system (i.e. the differential equations) is neverknown exactly, due to the presence of various small interactions. It is, therefore, crucial to know that basic features of the dynamics are the same for any small perturbation of the "model" system, whose evolution is governed by a certain known physical law. Qualitative analysis was further developed by George Birkhoff in the 1920s, but was first formalized with introduction of the concept of rough system by Andronov and Pontryagin in 1937. This was immediately applied to analysis of physical systems with oscillations by Andronov, Witt, and Khaikin. The term "structural stability" is due to Solomon Lefschetz, who oversaw translation of their monograph into English. Ideas of structural stability were taken up by Stephen Smale and his school in the 1960s in the context of hyperbolic dynamics. Earlier, Marston Morse and Hassler Whitney initiated and René Thom developed a parallel theory of stability for differentiable maps, which forms a key part of singularity theory. Thom envisaged applications of this theory to biological systems. Both Smale and Thom worked in direct contact with Maurício Peixoto, who developed Peixoto's theorem in the late 1950's.When Smale started to develop the theory of hyperbolic dynamical systems, he hoped that structurally stable systems would be "typical". This would have been consistent with the situation in low dimensions: dimension two for flows and dimension one for diffeomorphisms. However, he soon found examples of vector fields on higher-dimensional manifolds that cannot be made structurally stable by an arbitrarily small perturbation (such examples have been later constructed on manifolds of dimension three). This means that in higher dimensions, structurally stable systems are not dense. In addition, a structurally stable system may have transversal homoclinic trajectories of hyperbolic saddle closed orbits and infinitely many periodic orbits, even though the phase space is compact. The closest higher-dimensional analogue of structurally stable systems considered by Andronov and Pontryagin is given by the Morse–Smale systems.Structure theory of stability study was conducted on the mathematical model of the ideal, and the actual structure is not as ideal as mathematical model, in fact ,we need to consider the influence of various factors. For example ,for the compressive rods, load could not have absolute alignment section center; There will always be some initial bending bar itself, the so-called "geometric defects"; Material itself inevitably has some kind of "defect", such as the discreteness of yield stress and bar manufacturing methods caused by the residual stress, etc. So, in addition to the modulus of elasticity and geometry size of bar, all the above-mentioned factors affecting the bearing capacity of the push rod in different degrees, in the structure design of this influence often should be considered. Usually will be based on the ideal mathematical model to study the stability of thetheory is called buckling theory, based on the actual bar study consider the various factors related to the stability of the stability of the ultimate bearing capacity theory called the theory ofcrushing.Practical bar, component or structure damage occurred during use or as the loading test of the buckling load is called crushing load and ultimate bearing capacity. For simplicity, commonly used buckling load. About geometric defects, according to a large number of experimental results, it is generally believed to assume a meniscus curve and its vector degrees for the rod length of 1/1000. About tissue defects, in the national standard formula is not the same, allow the buckling stress curve given by the very different also, some problems remain to be further research.1.Steel structure stability design concept1.1.The difference between intensity and stabilityThe intensity refers to that the structure or a single component maximum stress (or internal force)caused by load in stable equilibrium state is more than the ultimate strength of building materials, so it is a question of the stress. The ultimate strength value is different according to the characteristics of the material varies. for steel ,it is the yield point. The research of stability is mainly is to find the external load and structure unstable equilibrium between internal resistance. That is to say, deformation began to rapid growth and we should try to avoid the structure entering the state, so it is a question of deformation. For example, for an axial compression columns, in the condition column instability, the lateral deflection of the column add a lot of additional bending moment, thus the fracture load of pillars can be far less than its axial compression strength. At this point, the instability is the main reason of the pillar fracture .1.2.The classification of the steel structure instability1)The stability problem with the equilibrium bifurcation(Branch point instability).2)The axial compression buckling of the perfect straight rod and tablet compression bucklingall belong to this category.3)The stability of the equilibrium bifurcation problem(Extreme value point instability).4)The ability of the loss of stability of eccentric compression member made of constructionsteel in plastic development to a certain degree , fall into this category.5)Jumping instability6)Jumping instability is a kind of different from the above two types of stability problem. Itis a jump to another stable equilibrium state after loss of stability balance.2.The principle of steel structure stability design2.1.For the steel structure arrangement, the whole system and the stability of the part requirements must be considered ,and most of the current steel structure is designed according to plane system, such as truss and frame. The overall layout of structure can guarantee that the flat structure does not appear out-of-plane instability,such as increasing the necessary supporting artifacts, etc. A planar structures of plane stability calculation is consistent with the structure arrangement.2.2.Structure calculation diagram should be consistent with a diagram of a practical calculation method is based on. When designing a single layer or multilayer frame structure, we usually do not make analysis of the framework stability but the frame column stability calculation. When we use this method to calculate the column frame column stability , the length factor should be concluded through the framework of the overall stability analysis which results in the equivalent between frame column stability calculation and stability calculation. For a single layer or multilayer framework, the column length coefficient of computation presented by Specification for design of steel structures (GB50017-2003) base on five basic assumptions. Including:all the pillars in the framework is the loss of stability at the same time, that is ,the critical load of the column reach at the same time. According to this assumes, each column stability parameters of the frame and bar stability calculation method, is based on some simplified assumptions or typical.Designers need to make sure that the design of structure must be in accordance with these assumptions.2.3.The detail structure design of steel structure and the stable calculation of component should be consistent. The guarantee that the steel structure detail structure design and component conforms to the stability of the calculation is a problem that needs high attention in the design of steel structure.Bending moment tonon-transmission bending moment node connection should be assigned to their enough rigidity and the flexibility.Truss node should minimize the rods' bias.But, when it comes to stability, a structure often have different in strength or special consideration. But requirement above in solving the beam overall stability is not enough.Bearing need to stop beam around the longitudinal axis to reverse,meanwhile allowing the beam in thein-plane rotation and free warp beam end section to conform to the stability analysis of boundary conditions. 3.The analysis method of the steel structure stabilitySteel structure stability analysis is directed at the outer loads under conditions of the deformation of structure.The deformation should be relative to unstability deformation of the structure or buckling. Deformation between load and structure is nonlinear relationship , which belongs to nonlinear geometric stability calculation and uses a second order analysis method. Stability calculated, both buckling load and ultimate load, can be regarded as the calculation of the stability bearing capacity of the structure or component.In the elastic stability theory, the calculation method of critical force can be mainly divided into two kinds of static method and energy method.3.1.Static methodStatic method, both buckling load and ultimate load, can be regarded as the calculation of the stability bearing capacity of the structure or component. Follow the basic assumptions in establishing balance differential equation:1)Components such as cross section is a straight rod.2)Pressure function is always along the original axis component3)Material is in accordance with hooke's law, namely the linear relationship between thestress and strain.4)Component accords with flat section assumption, namely the component deformation infront of the flat cross-section is still flat section after deformation.5)Component of the bending deformation is small ant the curvature can be approximatelyrepresented by the second derivative of the deflection function.Based on the above assumptions, we can balance differential equation,substitude into the corresponding boundary conditions and solve both ends hinged the critical load of axial compression component .3.2.Energy methodEnergy method is an approximate method for solving stability bearing capacity, through the principle of conservation of energy and potential energy in principle to solve the critical load values.1)The principle of conservation of energy to solve the critical loadWhen conservative system is in equilibrium state, the strain energy storaged in the structure is equal to the work that the external force do, namely, the principle of conservation of energy. As thecritical state of energy relations:ΔU =ΔWΔU—The increment of strain energyΔW—The increment of work forceBalance differential equation can be established by the principle of conservation of energy.2)The principle of potential energy in value to solve the critical load valueThe principle of potential energy in value refers to: For the structure by external force, when there are small displacement but the total potential energy remains unchanged,that is, the total potential energy with in value, the structure is in a state of balance. The expression is:dΠ=dU-dW =0dU—The change of the structure strain energy caused by virtual displacement , it is always positive;dW—The work the external force do on the virtual displacement;3.3.Power dynamics methodMany parts of the qualitative theory of differential equations and dynamical systems deal with asymptotic properties of solutions and the trajectories—what happens with the system after a long period of time. The simplest kind of behavior is exhibited by equilibrium points, or fixed points, and by periodic orbits. If a particular orbit is well understood, it is natural to ask next whether a small change in the initial condition will lead to similar behavior. Stability theory addresses the following questions: will a nearby orbit indefinitely stay close to a given orbit? will it converge to the given orbit (this is a stronger property)? In the former case, the orbit is called stable and in the latter case, asymptotically stable, or attracting. Stability means that the trajectories do not change too much under small perturbations. The opposite situation, where a nearby orbit is getting repelled from the given orbit, is also of interest. In general, perturbing the initial state in some directions results in the trajectory asymptotically approaching the given one and in other directions to the trajectory getting away from it. There may also be directions for which the behavior of the perturbed orbit is more complicated (neither converging nor escaping completely), and then stability theory does not give sufficient information about the dynamics.One of the key ideas in stability theory is that the qualitative behavior of an orbit under perturbations can be analyzed using the linearization of the system near the orbit. In particular, at each equilibrium of a smooth dynamical system with an n-dimensional phase space, there is acertain n×n matrix A whose eigenvalues characterize the behavior of the nearby points (Hartman-Grobman theorem). More precisely, if all eigenvalues are negative real numbers or complex numbers with negative real parts then the point is a stable attracting fixed point, and the nearby points converge to it at an exponential rate, cf Lyapunov stability and exponential stability. If none of the eigenvalues is purely imaginary (or zero) then the attracting and repelling directions are related to the eigenspaces of the matrix A with eigenvalues whose real part is negative and, respectively, positive. Analogous statements are known for perturbations of more complicated orbits.For the structure system in balance,if making it vibrate by applying small interference vibration,the structure of the deformation and vibration acceleration is relation to the structure load. When the load is less than the limit load of a stable value, the acceleration and deformation is in the opposite direction, so the interference is removed, the sports tend to be static and the structure of the equilibrium state is stable; When the load is greater than the ultimate load of stability, the acceleration and deformation is in the same direction, even to remove interference, movement are still divergent, therefore the structure of the equilibrium state is unstable. The critical state load is the buckling load of the structure,which can be made of the conditions that the structure vibration frequency is zero solution.At present, a lot of steel structure design with the aid of computer software for structural steel structure stress calculation, structure and component within the plane of strength and the overall stability calculation program automatically, can be counted on the structure and component of the out-of-plane strength and stability calculation, designers need to do another analysis, calculation and design. At this time the entire structure can be in the form of elevation is decomposed into a number of different layout structure, under different levels of load, the structure strength and stability calculation.local stability after buckling strength of the beam, it can be set up to the beam transverse or longitudinal stiffener, in order to solve the problem, the local stability of the beam stiffening rib according to Specification for Design of Steel Structures (GB50017-2003) ; Finite element analysis for a web after buckling strength calculation according to specification for design of steel structures (GB50017-2003) 4, 4 provisions. Axial compression member and a local bending component has two ways: one is the control board free overhanging flange width and thickness ratio of; The second is to control web computing the ratio of the height and thickness. For circular tube sectioncompression member, should control the ratio of outer diameter and wall thickness and stiffener according to specification for design of steel structures (GB50017-2003), 5 4 rule.4.ConclusionSteel structure has advantages of light weight, high strength and high degree of industrialization and has been widely used in the construction engineering.I believe that through to strengthen the overall stability and local stability of the structure and the design of out-of-plane stability, we could overcome structure design flaws and its application field will be more and more widely.referencesGB50017-2003,Design Code for Steel Structures[S]Chen Shaofan, Steel structure design principle [M]. Beijing: China building industry press, 2004 Kalman R.E. & Bertram J.F: Control System Analysis and Design via the Second Method of Lyapunov, J. Basic Engrg vol.88 1960 pp.371; 394LaSalle J.P. & Lefschetz S: Stability by Lyapunov's Second Method with Applications, New York 1961 (Academic)Smith M.J. and Wisten M.B., A continuous day-to-day traffic assignment model and the existence of a continuous dynamic user equilibrium , Annals of Operations Research, V olume 60, 1995 Arnold, V. I. (1988). Geometric methods in the theory of differential equations. Grundlehren der Mathematischen Wissenschaften, 250. Springer-Verlag, New York. ISBN 0-387-96649-8 Structural stability at Scholarpedia, curated by Charles Pugh and Maurício Matos Peixoto.。