二级公路毕业设计外文文献
二级公路设计英文参考文献
二级公路设计英文参考文献1. Manzini, R., & Sampath, A. (2015). Design of Rural Road Drainage Systems: A Simple and Effective Analysis Method. Journal of Transportation Engineering, 141(6), 04015014.This paper presents a simple and effective analysis method for designing drainage systems for rural roads. The authors propose a step-by-step approach that includes the determination of catchment areas, estimation of runoff volume, and evaluation of design criteria for culverts and ditches. The method is demonstrated through a case study in a rural area, highlighting its applicability and effectiveness.2. Gupta, A. K., & Kaul, S. K. (2012). Geometric Design of Rural Roads: A Case Study of Jammu & Kashmir in India. International Journal of Emerging Technology and Advanced Engineering, 2(6), 263-269.This case study focuses on the geometric design of rural roads in the Jammu & Kashmir region of India. The authors discuss the design considerations, such as road alignment, cross-section elements, sight distance, and horizontal and vertical curves. They also evaluate the current road design practices in the region and propose improvements based on internationally recognized standards.3. Pathak, N. C., & Das, L. P. (2010). Rural Road Design Guidelines for India. Journal of Transportation Engineering, 136(4), 342-351.This research article presents rural road design guidelines specifically tailored for India. The authors cover various aspects of road design, including alignment, cross-section elements, grading, drainage, and roadside development. The guidelines aim to improve safety and efficiency in the design of rural roads in India and are supported by extensive research and case studies.4. Qi, Y., Song, R., & Xu, W. (2014). Design of Pavement Structure for Rural Roads in Cold, High-Altitude Plateau Regions. Journal of Materials in Civil Engineering, 26(12), 04014065.This study focuses on the design of pavement structures for rural roads in cold, high-altitude plateau regions. The authors investigate the influence of climate, soil conditions, and traffic loads on pavement performance and propose a design method considering these factors. The research provides valuable insights for designing durable andcost-effective pavement structures in challenging environments.5. Thomet, M., Reutter, F., & Betz, F. (2017). Assessment of Safety Measures for Rural Roads: A Case Study in Switzerland. Transportation Research Procedia, 23, 551-558.This case study evaluates safety measures for rural roads in Switzerland. The authors analyze different road design elements, such as geometric design, signage, and delineation, in order to assess their impact on road safety. The findings contribute to the understanding of effective safety measures for rural roads and can inform future design decisions.。
二级公路毕业设计外文文献
外文资料及翻译Effects of Design Features on Rigid Pavement PerformanceThe performance of rigid pavements is affected by a variety of design features, including slab thickness, base type, joint spacing, reinforcement, joint orientation, load trans fer, dowel bar coatings, longitudinal joint design, joint sealant, tied concrete shoulders ,and subdrainage . A study was made by ERES Consultants, Inc. under FHWA contract on the effects of these features on rigid pavement performance . Ninety-five pavemen tsections located in four major climatic regions were thoroughly evaluated . The following conclusions, which provide some revealing insights into pavement performance, are abstracted from the report (Smith et al., 1990a).Slab Thickness The effect of slab thickness on pavement performance was significant.It was found that increasing slab thickness reduced transverse and longitudinal cracking in all cases. This effect was much more pronounced for thinner slabs than fo rthicker slabs . It was not possible to compare the performance of the thinner slabs and the thicker slabs directly, because the thick slabs were all constructed directly on th esubgrade and the thinner slabs were all constructed on a base course .Increasing the thickness of slab did not appear to reduce joint spalling or join tfaulting . Thick slabs placed directly on the subgrade, especially in wet climates an dexposed to heavy traffic, faulted as much as thin slabs constructed on a base course .Base Type Base types, including base/slab interface friction, base stiffness, base erodibility, and base permeability, seemed to have a great effect on the performance of jointed concrete pavements . The major performance indicators, which were affected by variations in base type, were transverse and longitudinal cracking, joint spalling, and faulting .The worst performing base type, consisted of the cement-treated or soil cement bases, which tended to exhibit excessive pumping, faulting, and cracking. This is most likely due to the impervious nature of the base, which traps moisture and yet can brea- k down and contribute to the movement of fines beneath the slab .The use of lean concrete bases generally produced poor performance . Large curl -ing and warping stresses have been associated with slabs constructed over lean concrete bases. These stresses result in considerable transverse and longitudinal cracking of the slab . The poor performance of these bases can also be attributed to a bathtub design, in which moisture is trapped within the pavement cross section .Dense-graded asphalt-treated base courses ranged in performance from very poor to good. The fact that these types of bases were often constructed as a bathtub design contributed to their poor performance . This improper design often resulted in severe cracking, faulting, and pumping.The construction of thicker slabs directly on the subgrade with no base resulted In a pavement that performed marginally. These pavements were especially susceptible to faulting, even under low traffic levels.Pavements constructed over aggregate bases had varied performance, but were generally in the fair to very good category. In general, the more open-graded the aggregate,the better the performance . An advantage of aggregate bases is that they contribute the least to the high curling and warping stresses in the slab . Even though aggregate bases are not open-graded, they are more permeable and have a lower friction factor than stabilized bases .The best bases in terms of pavement performance were the permeable bases . Typical base courses have permeabilities ranging from 0 to less than 1 ft/day (0 .3 m/day) ; good permeable bases have permeabilities up to 1000 ft/day (305 m/day) . Specific areas of concern were the high corner deflections and the low load transfer exhibited by the permeable bases . These can affect their long-term performance, so the use of dowel bars might be required . An unexpected benefit of using permeable bases was the reduction in "D" cracking on pavements susceptible to this type of distress .Slab Length For JPCP, the length of slabs investigated ranged from 7 .75 to 30 ft(2.4to9.1m). It was found that reducing the slab length decreased both the magnitude of the joint faulting and the amount of transverse cracking. On pavements with random joint spacings, slabs with joint spacings greater than 18 ft (5.5 m) experienced more transverse cracking than did the shorter slabs .For JRCP, the length of slabs investigated ranged from 21 to 78 ft (6 .4 to 23 .9 m) .Generally, shorter joint spacings performed better, as measured by the deteriorated transverse cracks, joint faulting, and joint spalling . However, several JRCP with long joint spacings performed quite well . In particular, the long jointed pavements in New Jersey, which were constructed with expansion joints, displayed excellent performance .An examination of the stiffness of foundation was made through the use of the radius of relative stiffness, f . Generally speaking, when the ratio L/E, where L is the length of slab, was greater than 5, transverse cracking occurred more frequently . Thisfactor was further examined for different base types . It was found that stiffer base courses required shorter joint spacings to reduce or eliminate transverse cracking .Reinforcement The amount of steel reinforcement appeared to have an effect in controlling the amount of deteriorated transverse cracking . Pavement sections with less than 0.1% reinforcing steel often displayed significant deteriorated transverse cracking.A minimum of 0 .1% reinforcing steel is therefore recommended, with larger amounts required for more severe climate and longer slabs.Joint Orientation Conventional wisdom has it that skewed joints prevent the application of two wheel loads to the joint at the same time and thus can reduce load-associated distresses . The results from the limited sample size in this study were ambiguous, but all of the nondoweled sections with skewed joints had a lower PSR than similar designs with perpendicular joints . The available data provide no definite conclusions on the effectiveness of skewing transverse joints for nondoweled slabs . Skewed joints are not believed to provide any benefit to doweled slabs.Load Transfer Dowel bars were found to be effective in reducing the amount of joint faulting when compared with nondoweled sections of comparable designs. The diameter of dowels had an effect on performance, because larger diameter bars provided better load transfer and control of faulting under heavy traffic than did smaller dowels.It appeared that a minimum dowel diameter of 1 .25 in . (32 mm) was necessary to provide good performance .Nondoweled JPCP slabs generally developed significant faulting, regardless of pavement design or climate . This effect was somewhat mitigated by the use of permeable bases. However, the sections in this group had a much lower number of accumulated ESAL, so no definite conclusions can be drawn yet .Dowel Bar Coatings Corrosion-resistant coatings are needed to protect dowels from the adverse effects of moisture and deicing chemicals .While most of the sections in this study did not contain corrosion-resistant dowel bars, those that did generally exhibited enhanced performance. Very little deteriorated transverse cracking was identified on these sections. In fact, one section in New Jersey with stainless steel-clad dowel bars was performing satisfactorily after 36 years of service .Longitudinal Joint Design The longitudinal joint design was found to be a critical design element.Both inadequate forming techniques and insufficient depths of joint can contribute to the development of longitudinal cracking . There was evidence of the ad vantage of sawing the joints over the use of inserts . The depth of longitudinal joints is generally recommended to be one-third of the actual, notdesigned, slab thickness, but might have to be greater when stabilized bases are used .Joint Sealant Joint sealing appeared to have a beneficial effect on performance . This was particularly true in harsh climates with excessive amounts of moisture . Preformed compression sealants were shown to perform well for more than 15 years under heavy traffic.Except where "D" cracking occurred, pavement sections containing preformed sealants generally exhibited little joint spalling and were in good overall conditions.Rubberized asphalt joint sealants showed good performance for 5 to 7 years.Tied Concrete Shoulders It is generally believed that tied concrete shoulders can reduce edge stresses and corner deflections by providing more lateral supports to the mainline pavement, thus improving pavement performance . Surprisingly, this study showed that, although tied concrete shoulders performed better than asphalt shoulders,many of the tied shoulders were not designed properly and actually contributed to poor performance of the mainline pavement . The tiebars were spaced too far apart ,sometimes at a spacing of 40 in.(1016 mm), and were not strategically located near slab corners to provide adequate support . In some cases, tied concrete shoulders were constructed over a stabilized dense-graded base in a bathtub design, resulting in the poor performance of mainline pavement.Subdrainage The provision of positive subdrainage, either in the form of longitudinal edge drains or the combination of a drainage layer and edge drains, generally reduced the amount of faulting and spalling related to "D" cracking . With few exceptions, the load-associated distresses, especially faulting and transverse cracking, decreased as the drainage characteristics improved . The overall pavement performance can be improved by using an open-graded base or restricting the percentage of fines . A filter layer must be placed below the permeable base, and regular maintenance of the outlets must be provided .译文结构特点对刚性路面性能的影响刚性路面的性能受种种结构特点的影响，如板厚、基层类型、接缝间距、钢筋用量、接风方向、荷载传递、传力杆涂层、纵缝设计、接缝填封料、有拉杆混凝土道肩和地下排水等。
公路路线设计毕业论文外文
公路路线设计毕业论文外文Design of Highway RouteIntroductionHighway transportation plays a vital role in modern society, enabling the efficient movement of goods and people. The design of a highway route is a crucial aspect that ensures safe and convenient travel for users. This paper aims to explore the key elements involved in the design of a highway route and provide an overview of the international practices and guidelines inthis field.Key Elements in Highway Route DesignInternational Practices and GuidelinesDifferent countries have developed their own practices and guidelines for highway route design. The United States, for example, follows the standards outlined in the "A Policy on Geometric Design of Highways and Streets" manual, also known as the Green Book. This manual provides detailed guidance on various design elements, such as alignment, cross-section, and geometrics. It emphasizes the importance of considering safety, mobility, and economic factors in the design process.The European Union has developed the "Eurocodes," a set of European standards for highway design. These codes provide guidelines for the design of various aspects, includingalignment, cross-section, and slope. They also emphasize the consideration of sustainability and environmental impact in the design process.ConclusionThe design of a highway route involves various key elements, including alignment, cross-section, slope, and geometrics. International practices and guidelines, such as the Green Book, Eurocodes, and Austroads design guidelines, provide valuable guidance in this field. It is essential for highway route designers to consider factors such as safety, environmental impact, and economic factors in the design process. By following these practices and guidelines, highway routes can be designed to ensure safe and convenient travel for users.。
道路工程毕业设计外文文献翻译
外文文献翻译原文:Asphalt Mixtures-Applications, Theory and Principles1 、ApplicationsAsphalt materials find wide usage in the construction industry、The use of asphalt as a cementing agent in pavements is the most common of its applications, however, and the one that will be consid ered here、Asphalt products are used to produce flexibl e pavements for highways and airports、The term “fl exible” is used to distinguish these pavements from those made with Portland cement, which are classified as rigid pavements, that is, having beam strength、This distinction is important because it provid es they key to the design approach which must be used for successful flexibl e pavement structures、The flexibl e pavement classification may be further broken d own into high and l ow types, the type usually depending on whether a solid or liquid asphalt product is used、The l ow types of pavement are mad e with the cutback, or emulsion, liquid products and are very widely used throughout this country、Descriptive terminol ogy has been developed in various sections of the country to the extent that one pavement type may have several names、However, the general process foll owed in construction is similar for most l ow-type pavements and can be described as one in which the aggregate and the asphalt product are usually applied to the roadbed separately and there mixed or all owed to mix, forming the pavement、The high type of asphalt pavements is made with asphalt cements of some sel ected penetration grad e、Fig、·1 A modern asphalt concrete highway、Shoul der striping is used as a safely feature、Fig、·2 Asphalt concrete at the San Francisco International Airport、They are used when high wheel l oads and high volumes of traffic occur and are, therefore, often designed for a particular installation、2 、Theory of asphalt concrete mix designHigh types of flexible pavement are constructed by combining an asphalt cement, often in the penetration grad e of 85 to 100, with aggregates that are usually divided into three groups, based on size、The three groups are coarse aggregates, fine aggregates, and mineral filler、These will be discussed in d etail in later chapter、Each of the constituent parts mentioned has a particular function in the asphalt mixture, and mix proportioning or d esign is the process of ensuring that no function is negl ected、Before these individual functions are examined, however, the criteria for pavement success and failure should be consid ered so that d esign objectives can be established、A successful fl exible pavement must have several particular properties、First, it must be stable, that is to resistant to permanent displacement under l oad、Deformation of an asphaltpavement can occur in three ways, two unsatisfactory and one desirable、Plastic deformation of a pavement failure and which is to be avoid ed if possible、Compressive deformation of the pavement results in a dimensional change in the pavement, and with this change come a l oss of resiliency and usually a d egree of roughness、This d eformation is less serious than the one just described, but it, too, leads to pavement failure、The desirable type of deformation is an elastic one, which actually is beneficial to flexibl e pavements and is necessary to their long life、The pavement should be durable and should offer protection to the subgrade、Asphalt cement is not impervious to the effects of weathering, and so the design must minimize weather susceptibility、A durable pavement that d oes not crack or ravel will probably also protect the roadbed、It must be remembered that flexible pavements transmit loads to the subgrad e without significant bridging action, and so a dry firm base is absolutely essential、Rapidly moving vehicl es d epend on the tire-pavement friction factor for control and safety、The texture of the pavement surfaces must be such that an adequate skid resistance is developed or unsafe conditions result、The design procedure shoul d be used to select the asphalt material and aggregates combination which provid es a skid resistant roadway、Design procedures which yield paving mixtures embodying all these properties are not available、Sound pavements are constructed where materials and methods are selected by using time-tested tests and specifications and engineering judgments al ong with a so-call ed design method、The final requirement for any pavement is one of economy、Economy, again, cannot be measured directly, since true economy only begins with construction cost and is not fully determinable until the full useful life of the pavement has been record ed、If, however, the requirements for a stable, durable, and safe pavement are met with a reasonable safety factor, then the best interests of economy have probably been served as well、With these requirements in mind, the functions of the constituent parts can be examined with consideration give to how each part contributes to now-established objectives or requirements、The functions of the aggregates is to carry the load imposed on the pavement, and this is accomplished by frictional resistance and interl ocking between the individual pieces of aggregates、The carrying capacity of the asphalt pavement is, then, related to thesurface texture (particularly that of the fine aggregate) and the density, or “compactness,”, of the aggregates、Surface texture varies with different aggregates, and while a rough surface texture is desired, this may not be available in some l ocalities、Dense mixtures are obtained by using aggregates that are either naturally or artificially “well graded”、This means that the fine aggregate serves to fill the voids in the coarser aggregates、In addition to affecting density and therefore strength characteristics, the grading also influences workability、When an excess of coarse aggregate is used, the mix becomes harsh and hard to work、When an excess of mineral filler is used, the mixes become gummy and difficult to manage、The asphalt cement in the fl exibl e pavement is used to bind the aggregate particl es together and to waterproof the pavements、Obtaining the proper asphalt content is extremely important and bears a significant influence on all the items marking a successful pavement、A chief objective of all the design methods which have been devel oped is to arrive at the best asphalt content for a particular combination of aggregates、3 、Mix design principl esCertain fundamental principles underlie the design procedures that have been developed、Before these procedures can be properly studied or applied, some consid eration of these principles is necessary、Asphalt pavements are composed of aggregates, asphalt cement, and voids、Considering the aggregate alone, all the space between particles is void space、The volume of aggregate voids depends on grading and can vary widely、When the asphalt cement is add ed, a portion of these aggregate voids is filled and a final air-void volume is retained、The retention of this air-void volume is very important to the characteristics of the mixture、The term air-void volume is used, since these voids are weightless and are usually expressed as a percentage of the total volume of the compacted mixture、An asphalt pavement carries the applied load by particl e friction and interlock、If the particl es are pushed apart for any reason , then the pavement stability is d estroyed、This factor indicates that certainly no more asphalt shoul d be ad ded than the aggregate voids can readily hold、However ,asphalt cement is susceptibl e to volume change and the pavement is subject to further compaction under use、If the pavement has no air voids when placed, or if it loses them under traffic, then the expanding asphalt will overfl ow in a condition known asbleeding、The l oss of asphalt cement through bleeding weakens the pavement and also reduces surface friction, making the roadway hazard ous、Fig、·3 Cross section of an asphalt concrete pavement showing the aggregate framework bound together by asphalt cement、The need for a minimum air-void volume (usually 2 or 3 per cent ) has been established、In addition, a maximum air-void volume of 5 to 7 per cent shoul d not be exceed、An excess of air voids promotes raveling of the pavement and also permits water to enter and speed up the deteriorating processes、Also, in the presence of excess air the asphalt cement hardens and ages with an accompanying loss of durability and resiliency、The air-void volume of the mix is determined by the d egree of compaction as well as by the asphalt content、For a given asphalt content, a lightly compacted mix will have a large voids volume and a l ower d ensity and a greater strength will result、In the laboratory, the compaction is controlled by using a specified hammer and regulating the number of bl ows and the energy per blow、In the field, the compaction and the air voids are more difficult to control and tests must be made no specimens taken from the compacted pavement to cheek on the d egree of compaction being obtained、Traffic further compact the pavement, and all owance must be mad e for this in the design、A systematic checking of the pavement over an extended period is need ed to given factual information for a particular mix、A change in density of several per cent is not unusual, however、Asphalt content has been discussed in connection with various facets of the ix design problem、It is a very important factor in the mix design and has a bearing an all the characteristics ld a successful pavement: stability, skid resistance, durability, and economy、As has been mentioned, the various d esign procedures are intended to provide a means for selecting the asphalt content 、These tests will be considered in detail in a future chapter ,but the relationship between asphalt content and the measurable properties of stability, unit weight, and air voids will be discussed here、Fig、4 Variations in stability, unit weight, and air-void content with asphalt cement content、If the gradation and type of aggregate, the degree of compaction, and the type of asphalt cement are controll ed, then the strength varies in a predictable manner、The strength will increase up to some optimum asphalt content and then decrease with further additions、The pattern of strength variation will be different when the other mix factors are changed, and so only a typical pattern can be predicted prior to actual testing、Unit weight varies in the same manner as strength when all other variabl e arecontroll ed、It will reach some peak value at an asphalt content near that determined from the strength curve and then fall off with further additions、As already mentioned, the air-void volume will vary with asphalt content、However, the manner of variation is different in that increased asphalt content will d ecrease air-void volume to some minimum value which is approached asymptotically、With still greater additions of asphalt material the particles of aggregate are only pushed apart and no change occurs in air-void volume、In summary, certain principles involving aggregate gradation, air-void volume, asphalt content, and compaction mist be understood before proceeding to actual mix d esign、The proper design based on these principl es will result in sound pavements、If these principles are overlooked, the pavement may fail by one or more of the recognized modes of failure: shoving, rutting, corrugating, becoming slick when the max is too ‘rich’; raveling, cracking,having low durability when t he mix is too ‘l ean’、It should be again emphasized that the strength of flexible is, more accurately, a stability and d oes not indicate any ability to bridge weak points in the subgrade by beam strength、No asphalt mixture can be successful unless it rests on top of a properly designed and constructed base structure、This fact, that the surface is no better than the base, must be continually in the minds of those concerned with any aspect of fl exible pavement work、译文:沥青混合料的应用、理论与原则1、应用沥青材料如今在建筑行业广泛使用。
毕设中英文摘要--铁炉子二级公路山岭隧道毕业设计
随着社会的发展，公路隧道在高等级公路中得到广泛应用。
由于它在山岭地区有克服地形或高程障碍，改善线形，提高车速，缩短里程，节约燃料，节省时间，减少对植被的破坏，保护生态环境等优点。
本设计课题为铁炉子二级公路山岭隧道结构设计，注重的是结构计算，重点研究新奥法施工。
在设计中，首先依据隧道设计规范、结合围岩类型和周围环境对隧道进行选址，并且选择合理的洞门形式及其验算洞门的稳定性。
其次根据洞身所处围岩级别和埋深的不同进行了隧道的围岩压力计算和结构静力计算，根据使用工程类比法来选择支护参数，并且依据围岩压力来进行衬砌配筋计算及其支护参数安全稳定性验算。
然后是根据工程需要选择合理的施工监测方案，通过多种量测手段，对开挖后隧道围岩进行动态监测，并以此知道隧道支护结构的设计与施工。
最后，还根据隧道工程特点、施工技术装备和施工力量等技术与经济因素，在确保安全、经济的前提下，编制隧道施工组织设计。
在设计中，还加入了许多的比选，或者备选方案，在对各项方案的选择时，结合长径隧道的实际特点选定最适合的一种作为最终方案。
这样，对加深隧道结构的认识，施工工艺方法的了解和对检测项目实施完整性准确性的把握都很有好处。
关键词：隧道设计；新奥法；围岩压力；衬砌支护；施工组织With the development of society, highway tunnels are widely used in the high-grade highways. They can overcome obstacles to the terrain or elevation, to improve alignment and enhance the speed and shorten the mileage, save fuel, save time, reduce the destruction of vegetation has the advantages of protecting the environment.The design issue for Secondary roads of the Tie Lu Zi, the structure-oriented computing, focuses on the construction of the new Austrian law. In the design, the first tunnel in accordance with design specifications, combined with rock type and the surrounding environment of the tunnel entrance to the site, and choose a reasonable form of the portal and check the stability of Portal. Second, under the rock where holes are different levels and depth of the tunnel to the rock pressure calculation and calculation of static structure, in accordance with the use of analogy works to select the initial parameters and the second pit lining support parameters, and based on Wai rock reinforcement lining pressure to support the calculation and checking security and stability of parameters. Is based on the project and then need to select a reasonable construction of the monitoring program, through a variety of means of measurement, the tunnel after excavation for dynamic monitoring, and to know that the tunnel support structure design and construction. Finally, also in accordance with the characteristics of tunnel engineering, construction technology and equipment and construction forces and economic factors such as technology, in ensuring the security, economic, under the premise of the preparation of the tunnel construction organization design.In the design, but also adding a lot more than elections or options in the choice of the program, the combined length of the actual characteristics of the tunnel to choose the most suitable one as the final stage. Such as the choice of excavation methods, the law in the whole cross-section, step method, the law division of the excavation were compared, and finally integration of the various ways the characteristics of excavation and grade Ⅴ the inherent characteristics of surrounding areas, selected Division CRD law excavation method. In this way, to deepen understanding of the tunnel structure, construction techniques and methods to understand the integrity of testing the accuracy of the implementation of the project are very good grasp.Key words: Long-track tunnel ；Tunnel design ；Rock pressureLining ；Construction organizations。
道路交通工程专业外文翻译外文文献英文文献
土木工程学院交通工程专业中英文翻译Road Design专业：交通工程英文原文The Basics of a Good RoadWe have known how to build good roads for a long time. Archaeologists have found ancient Egyptian roadsthat carried blocks to the pyramids in 4600 BCE. Later,the Romans built an extensive road system, using the same principles we use today. Some of these roads arestill in service.If you follow the basic concepts of road building, you will create a road that will last. The ten commandments of a good road are:（1）Get water away from the road（2）Build on a firm foundation（3）Use the best materials（4）Compact all layers properly（5）Design for traffic loads and volumes（6）Design for maintenance（7）Pave only when ready（8）Build from the bottom up（9）Protect your investment（10）Keep good records1．Get water away from the roadWe can’t overemphasize the importance of good drainage.Engineers estimate that at least 90% of a road’s problems can be related to excess water or to poor waterdrainage. Too much water in any laye r of a road’sstructure can weaken that layer, leading to failure.In the surface layer, water can cause cracks and potholes. In lower layers it undermines support, causing cracks and potholes. A common sign of water in an asphalt road surface is alligator cracking — an interconnected pattern of cracks forming small irregular shaped pieces that look like alligator skin. Edge cracking, frost heaves, and spring breakup of pavements also point to moisture problems.To prevent these problems remember that water:• flows downhill• needs to flow someplace• is a problem if it is not flowingEffective drainage systems divert, drain and dispose of water. To do this they use interceptor ditches and slopes,road crowns, and ditch and culvert systems.Divert —Interceptor ditches, located between the road and higher ground along the road, keep the water from reaching the roadway. These ditches must slope so they carry water away from the road.Drain —Creating a crown in the road so it is higher along the centerline than at the edges encourages water to flow off the road. Typically a paved crown should be 1⁄4" higher than the shoulder for each foot of width from the centerline to the edge. For gravel surfaces the crownshould be 1⁄2" higher per foot of width. For this flow path to work, the road surface must be relatively water tight. Road shoulders also must be sloped away from the road to continue carrying the flow away. Superelevations (banking) at the outside of curves will also help drainthe road surface.Dispose —A ditch and culvert system carries water away from the road structure. Ditches should be at least one foot lower than the bottom of the gravel road layer that drains the roadway. They must be kept clean and must be sloped to move water into natural drainage. If water stays in the ditches it can seep back into the road structure and undermine its strength. Ditches should also be protected from erosion by planting grass, or installing rock and other erosion control measures. Erosion can damage shoulders and ditches, clog culverts, undermine roadbeds, and contaminate nearby streams and lakes. Evaluate your ditch and culvert system twice a year to ensure that it works. In the fall, clean out leaves and branches that can block flow. In spring, check for and remove silts from plowing and any dead plant material left from the fall.2．Build on a firm foundationA road is only as good as its foundation. A highway wears out from the top down but falls apart from the bottom. The road base must carry the entire structure and the traffic that uses it.To make a firm foundation you may need to stabilize the roadbed with chemical stabilizers, large stone called breaker run, or geotextile fabric. When you run into conditions where you suspect that the native soil is unstable, work with an engineer to investigate the situation and design an appropriate solution.3．Use the best materialsWith all road materials you “pay now or pay later.” Inferior materials may require extensive maintenance throughout the road’s life. They may also force you to replace the road prematurely.Crushed aggregate is the best material for the base course. The sharp angles of thecrushed material interlock when they are compacted. This supports the pavement and traffic by transmitting the load from particle to particle. By contrast, rounded particles act like ballbearings, moving under loads.Angular particles are more stable than rounded particles.Asphalt and concrete pavement materials must be of the highest quality, designed forthe conditions, obtained from established firms, and tested to ensure it meets specifications.4．Compact all layersIn general, the more densely a material is compacted, the stronger it is. Compaction also shrinks or eliminates open spaces (voids) between particles. This means that less water can enter the structure. Water in soil can weaken the structure or lead to frost heaves. This is especially important for unsurfaced (gravel) roads. Use gravel which has a mix of sizes (well-graded aggregate) so smaller particles can fill the voids between larger ones. Goodcompaction of asphalt pavement lengthens its life.5．Design for traffic loads and volumesDesign for the highest anticipated load the road will carry. A road that has been designed only for cars will not stand up to trucks. One truck with 9 tons on a single rear axle does as much damage to a road as nearly 10,000 cars.Rural roads may carry log trucks, milk trucks, fire department pumper trucks, or construction equipment. If you don’t know what specific loads the road w ill carry, a good rule of thumb is to design for the largest piece of highway maintenance equipment that will be used on the road.A well-constructed and maintained asphalt road should last 20 years without major repairs or reconstruction. In designing a road, use traffic counts that project numbers and sizes of vehicles 20 years into the future. These are only projections, at best, but they will allow you to plan for traffic loadings through a road’s life.6．Design for maintenanceWithout maintenance a road will rapidly deteriorate and fail. Design your roads so they can be easily maintained. This means:• adequate ditches that can be cleaned regularly• culverts that are marked for easy locating in the spring• enough space for snow after it is plowed off the road• proper cross slopes for safety, maintenance and to avoid snow drifts• roadsi des that are planted or treated to prevent erosion• roadsides that can be mowed safelyA rule of thumb for adequate road width is to make it wide enough for a snowplow to pass another vehicle without leaving the travelled way.Mark culverts with a post so they can be located easily.7．Pave only when readyIt is not necessary to pave all your roads immediately. There is nothing wrong with a well-built and wellmaintained gravel road if traffic loads and volume do not require a paved surface. Three hundred vehicles per day is the recommended minimum to justify paving.Don’t assume that laying down asphalt will fix a gravel road that is failing. Before youpave, make sure you have an adequate crushed stone base that drains well and is properly compacted. The recommended minimum depth of crushed stone base is 10" depending on subgrade soils. A road paved only when it is ready will far outperform one that is constructed too quickly.8．Ê Build from the bottom upThis commandment may seem obvious, but it means that you shouldn’t top dress or resurface a road if the problem is in an underlying layer. Before you do any road improvement, locate the cause of any surface problems. Choose an improvement technique that will address the problem. This may mean recycling or removing all road materials down to the native soil and rebuilding everything. Doing any work that doesn’t solve the problem is a waste of money and effort.9．Ê Protec t your investmentThe road system can be your municipality’s biggest investment. Just as a home needs painting or a new roof, a road must be maintained. Wisconsin’s severe climate requires more road maintenance than in milder places. Do these important maintenance activities: Surface —grade, shape, patch, seal cracks, control dust, remove snow and iceDrainage —clean and repair ditches and culverts; remove all excess materialRoadside —cut brush, trim trees and roadside plantings, control erosionTraffic service —clean and repair or replace signsDesign roads with adequate ditches so they can be maintained with a motor grader. Clean and grade ditches to maintain proper pitch and peak efficiency. After grading, remove all excess material from the shoulder.10．Keep good recordsYour maintenance will be more efficient with good records. Knowing the road’s construction, life, and repair history makes it much easier to plan and budget its future repairs. Records can also help you evaluate the effectiveness of the repair methods and materials you used.Good record keeping starts with an inventory of the system. It should include the history and surface condition of the roadway, identify and evaluate culverts and bridges, note ditch conditions, shoulders, signs, and such structures as retaining walls and guardrails.Update your inventory each year or when you repair or change a road section. A formal pavement management system can help use these records and plan and budget road improvements.ResourcesThe Basics of a Good Road#17649, UW-Madison, 15 min. videotape. Presentsthe Ten Commandments of a Good Road. Videotapes are loaned free through County Extension offices.Asphalt PASER Manual(39 pp), Concrete PASER Manual (48 pp), Gravel PASERManual (32 pp). These booklets contain extensive photos and descriptions of road surfaces to help you understand types of distress conditions and their causes. A simple procedure for rating the condition helps you manage your pavements and plan repairs.Roadware, a computer program which stores and reports pavement conditioninformation. Developed by the Transportation Information Center and enhanced by the Wisconsin Department of Transportation, it uses the PASER rating system to providefive-year cost budgets and roadway repair/reconstruction priority lists.Wisconsin Transportation Bulletin factsheets, available from the Transportation Information Center (T.I.C.).Road Drainage, No. 4. Describes drainage for roadways, shoulders, ditches, and culverts.Gravel Roads, No. 5. Discusses the characteristics of a gravel road and how to maintain one.Using Salt and Sand for Winter Road Maintenance,No. 6. Basic information and practical tips on how to use de-icing chemicals and sand.Culverts—Proper Use and Installation, No. 15. Selecting and sizing culverts, designing, installing and maintaining them.Geotextiles in Road Construction/Maintenance andErosion Control, No. 16. Definitions and common applications of geotextiles onroadways and for erosion control.T.I.C. workshops are offered at locations around the state.Crossroads,an 8-page quarterly newsletter published by the T.I.C. carries helpfularticles, workshop information, and resource lists. For more information on any of these materials, contact the T.I.C. at 800/442-4615.中文译文一个良好的公路的基础长久以来我们已经掌握了如何铺设好一条道路的方法，考古学家发现在4600年古埃及使用建造金字塔的石块铺设道路，后来，罗马人使用同样的方法建立了一个庞大的道路系统，这种方法一直沿用到今天。
交通毕业设计外文及翻译（最终五篇）
交通毕业设计外文及翻译（最终五篇）第一篇：交通毕业设计外文及翻译Synchro在交通控制与设计中的应用在城市的较小的区域内，可以对区域内的所有交叉口进行控制;在城市较大的区域，可以对区域进行分区分级控制。
分区的结果往往使面控制成为一个由几条线控制组成的分级集中控制系统，这时，可认为各线控制是面控制中的一个单元；有时分区的结果是成为一个点，线，面控制的综合性分级控制系统。
现在对城市道路进行区域协调控制就是将其划分为多级多个信号控制子区，对信号子区进行协调控制，优化管理控制信号子区，然后对整个道路进行区域协调控制，达到整个城市道路优化的目的。
把城市道路划分为多个信号控制子区，也就是进行城市道路干线交叉口交通信号协调控制，把城市划分为多个主路控制，再把主路上各个交叉口进行联动控制，同时，对单个交叉口信号控制优化的同时需要考虑主路上下游各个交叉口的联动控制。
主路上的各个交叉口按照设计的信号配时方案进行运行，使车辆进入城市主干道交叉口时，不至经常遇到红灯，称为城市主干道交叉口信号协调控制，称为“绿波”信号控制。
城市单点交叉口作为城市交通网络中的重要组成部分，作为城市道路交通问题的关键点。
对城市单点交叉口，评价标准的参考指标：交叉口的通行能力、进口道的饱和度、道路交叉口进口道停车延误、交叉口进口道停车次数、进口道排队长度和汽车的油耗等。
交叉口定时信号控制配时方法在不断的改进之中，国内外大部分学者认为从不同的评价指标出发，可以采用不同的种优化算法寻求其它更合理的配时方法。
平面交叉口按交通管制方式可以分为全无控制交叉口、主路优先控制交叉口、信号灯控制交叉口、环形交叉口等几种类型。
主路优先控制交叉口，是在次路上设停车让行或减速让行标志，指令次路车辆必须停车或减速让主路车辆优先通行的一种交通管制方式。
交叉口是道路网中通行能力的“瓶颈”和交通事故的“黑点”。
国内外城市中的交通堵塞主要发上在交叉口，造成车辆中断，事故增多，延误严重。
毛嘴K6+000至小李湾K9+000二级公路设计专业外文翻译
本科毕业设计（论文）专业名称： 土木工程专业（道路与桥梁）年级班级：道桥08-5班 学生姓名：宋鹏 指导教师：廖明成河南理工大学土木工程学院二○一二年五月十八日专业外文翻译Geometric Design of HighwaysThe road is one kind of linear construction used for travel. It is made of the roadbed, the road surface, the bridge, the culvert and the tunnel. In addition, it also has the crossing of lines, the protective project and the traffic engineering and the route facility.The roadbed is the base of road surface, road shoulder, side slope, side ditch foundations. It is stone material structure, which is designed according to route's plane position .The roadbed, as the base of travel, must guarantee that it has the enough intensity and the stability that can prevent the water and other natural disaster from corroding.The road surface is the surface of road. It is single or complex structure built with mixture. The road surface require being smooth, having enough intensity, good stability and anti-slippery function. The quality of road surface directly affects the safe, comfort and the traffic.Highway geometry designs to consider Highway Horizontal Alignment, Vertical Alignment two kinds of linear and cross-sectional composition of coordination, but also pay attention to the smooth flow of the line of sight, etc. Determine the road geometry, consider the topography, surface features, rational use of land and environmental protection factors, to make full use of the highway geometric components of reasonable size and the linear combination.1.Alignment DesignThe alignment of a road is shown on the plane view and is a series of straight lines called tangents connected by circular. In modern practice it is common to interpose transition or spiral curves between tangents and circular curves.Alignment must be consistent. Sudden changes from flat to sharp curves and long tangents followed by sharp curves must be avoided; otherwise, accident hazards will be created. Likewise, placing circular curves of different radii end to end (compound curves) or having a short tangent between two curves is poor practice unless suitable transitions between them are provided. Long, flat curves are preferable at all times, as they are pleasing in appearance and decrease possibility of futureobsolescence. However, alignment without tangents is undesirable on two-lane roads because some drivers hesitate to pass on curves. Long, flat curves should be used for small changes in direction, as short curves appear as “kink”. Also horizontal and vertical alignment must be considered together, not separately. For example, a sharp horizontal curve beginning near a crest can create a serious accident hazard.A vehicle traveling in a curved path is subject to centrifugal force. This is balanced by an equal and opposite force developed through cannot exceed certain maximums, and these controls place limits on the sharpness of curves that can be used with a design speed. Usually the sharpness of a given circular curve is indicated by its radius. However, for alignment design, sharpness is commonly expressed in terms o f degree of curve, which is the central angle subtended by a 100-ft length of curve. Degree of curve is inversely proportional to the radius.Tangent sections of highways carry normal cross slope; curved sections are super elevated. Provision must be made for gradual change from one to the other. This usually involves maintaining the center line of each individual roadway at profile grade while raising the outer edge and lowering the inner edge to produce the desired super elevation is attained some distance beyond the point of curve.If a vehicle travels at high speed on a carefully restricted path made up of tangents connected by sharp circular curve, riding is extremely uncomfortable. As the car approaches a curve, super elevation begins and the vehicle is tilted inward, but the passenger must remain vertical since there is on centrifugal force requiring compensation. When the vehicle reaches the curve, full centrifugal force develops at once, and pulls the rider outward from his vertical position. To achieve a position of equilibrium he must force his body far inward. As the remaining super elevation takes effect, further adjustment in position is required. This process is repeated in reverse order as the vehicle leaves the curve. When easement curves are introduced, the change in radius from infinity on the tangent to that of the circular curve is effected gradually so that centrifugal force also develops gradually. By careful application of super elevation along the spiral, a smooth and gradual application of centrifugal force can be had and the roughness avoided.Easement curves have been used by the railroads for many years, but their adoption by highway agencies has come only recently. This is understandable. Railroad trains must follow the precise alignment of the tracks, and the discomfort described here can be avoided only by adopting easement curves. On the other hand, the motor-vehicle operator is free to alter his lateral position on the road and can provide his own easement curves by steering into circular curves gradually. However, this weaving within a traffic lane (but sometimes into other lanes) is dangerous. Properly designed easement curves make weaving unnecessary. It is largely for safety reasons, then, that easement curves have been widely adopted by highway agencies.For the same radius circular curve, the addition of easement curves at the ends changes the location of the curve with relation to its tangents; hence the decision regarding their use should be made before the final location survey. They point of beginning of an ordinary circular curve is usually labeled the PC (point of curve) or BC (beginning of curve). Its end is marked the PT (point of tangent) or EC (end of curve). For curves that include easements, the common notation is, as stationing increases: TS (tangent to spiral), SC (spiral to circular curve), CS (circular curve to spiral), and ST (spiral go tangent).On two-lane pavements provision of a wilder roadway is advisable on sharp curves. This will allow for such factors as (1) the tendency for drivers to shy away from the pavement edge, (2) increased effective transverse vehicle width because the front and rear wheels do not track, and (3) added width because of the slanted position of the front of the vehicle to the roadway centerline. For 24-ft roadways, the added width is so small that it can be neglected. Only for 30mph design speeds and curves sharper than 22°does the added width reach 2 ft. For narrower pavements, however, widening assumes importance even on fairly flat curves. Recommended amounts of and procedures for curve widening are given in Geometric Design for Highways.2. GradesThe vertical alignment of the roadway and its effect on the safe and economical operation of the motor vehicle constitute one of the most important features of road design. The vertical alignment, which consists of a series of straight lines connected by vertical parabolic or circular curves, is known as the “grade line.” When the gradeline is increasing from the horizontal it is known as a “plus grade,” and when it is decreasing from the horizontal it is known as a “minus grade.” In analyzing grade and grade controls, the designer usually studies the effect of change in grade on the centerline profile.In the establishment of a grade, an ideal situation is one in which the cut is balanced against the fill without a great deal of borrow or an excess of cut to be wasted. All hauls should be downhill if possible and not too long. The grade should follow the general terrain and rise and fall in the direction of the existing drainage. In mountainous country the grade may be set to balance excavation against embankment as a clue toward least overall cost. In flat or prairie country it will be approximately parallel to the ground surface but sufficiently above it to allow surface drainage and, where necessary, to permit the wind to clear drifting snow. Where the road approaches or follows along streams, the height of the grade line may be dictated by the expected level of flood water. Under all conditions, smooth, flowing grade lines are preferable to choppy ones of many short straight sections connected with short vertical curves.Changes of grade from plus to minus should be placed in cuts, and changes from a minus grade to a plus grade should be placed in fills. This will generally give a good design, and many times it will avoid the appearance of building hills and producing depressions contrary to the general existing contours of the land. Other considerations for determining the grade line may be of more importance than the balancing of cuts and fills.Urban projects usually require a more detailed study of the controls and finer adjustment of elevations than do rural projects. It is often best to adjust the grade to meet existing conditions because of the additional expense of doing otherwise.In the analysis of grade and grade control, one of the most important considerations is the effect of grades on the operating costs of the motor vehicle. An increase in gasoline consumption and a reduction in speed are apparent when grades are increase in gasoline consumption and a reduction in speed is apparent when grades are increased. An economical approach would be to balance the added annual cost of grade reduction against the added annual cost of vehicle operation without grade reduction. An accurate solution to the problem depends on the knowledge of trafficvolume and type, which can be obtained only by means of a traffic survey.While maximum grades vary a great deal in various states, AASHTO recommendations make maximum grades dependent on design speed and topography. Present practice limits grades to 5 percent of a design speed of 70 mph. For a design speed of 30 mph, maximum grades typically range from 7 to 12 percent, depending on topography. Wherever long sustained grades are used, the designer should not substantially exceed the critical length of grade without the provision of climbing lanes for slow-moving vehicles. Critical grade lengths vary from 1700 ft for a 3 percent grade to 500 ft for an 8 percent grade.Long sustained grades should be less than the maximum grade on any particular section of a highway. It is often preferred to break the long sustained uniform grade by placing steeper grades at the bottom and lightening the grade near the top of the ascent. Dips in the profile grade in which vehicles may be hidden from view should also be avoided. Maximum grade for highway is 9 percent. Standards setting minimum grades are of importance only when surface drainage is a problem as when water must be carried away in a gutter or roadside ditch. In such instances the AASHTO suggests a minimum of 0.35%.3. Sight DistanceFor safe vehicle operation, highway must be designed to give drivers a sufficient distance or clear version ahead so that they can avoid unexpected obstacles and can pass slower vehicles without danger. Sight distance is the length of highway visible ahead to the driver of a vehicle. The concept of safe sight distance has two facets: “stopping” (or “no passing”) and “passing”.At times large objects may drop into a roadway and will do serious damage to a motor vehicle that strikes them. Again a car or truck may be forced to stop in the traffic lane in the path of following vehicles. In dither instance, proper design requires that such hazards become visible at distances great enough that drivers can stop before hitting them. Further more, it is unsafe to assume that one oncoming vehicle may avoid trouble by leaving the lane in which it is traveling, for this might result in loss of control or collision with another vehicle.Stopping sight distance is made up of two elements. The first is the distancetraveled after the obstruction comes into view but before the driver applies his brakes. During this period of perception and reaction, the vehicle travels at its initial velocity. The second distance is consumed while the driver brakes the vehicle to a stop. The first of these two distances is dependent on the speed of the vehicle and the perception time and brake-reaction time of the operator. The second distance depends on the speed of the vehicle; the condition of brakes, times, and roadway surface; and the alignment and grade of the highway.On two-lane highways, opportunity to pass slow-moving vehicles must be provided at intervals. Otherwise capacity decreases and accidents increase as impatient drivers risk head-on collisions by passing when it is unsafe to do so. The minimum distance ahead that must be clear to permit safe passing is called the passing sight distance. In deciding whether or not to pass another vehicle, the driver must weigh the clear distance available to him against the distance required to carry out the sequence of events that make up the passing maneuver. Among the factors that will influence his decision are the degree of caution that he exercises and the accelerating ability of his vehicle. Because humans differ markedly, passing practices, which depend largely on human judgment and behavior rather than on the laws of mechanics, vary considerably among drivers.The geometric design is to ensure highway traffic safety foundation, the highway construction projects around the other highway on geometric design, therefore, in the geometry of the highway design process, if appear any unsafe potential factors, or low levels of combination of design, will affect the whole highway geometric design quality, and the safety of the traffic to bring adverse impact. So, on the geometry of the highway design must be focus on.公路几何设计公路是供汽车或其他车辆行驶的一种线形带状结构体。
交通工程专业外文翻译外文文献英文文献
土木工程学院交通工程专业中英文翻译Road Design专业：交通工程英文原文The Basics of a Good RoadWe have known how to build good roads for a long time. Archaeologists have found ancient Egyptian roadsthat carried blocks to the pyramids in 4600 BCE. Later,the Romans built an extensive road system, using the same principles we use today. Some of these roads are still in service.If you follow the basic concepts of road building, you will create a road that will last. The ten commandments of a good road are:（1）Get water away from the road（2）Build on a firm foundation（3）Use the best materials（4）Compact all layers properly（5）Design for traffic loads and volumes（6）Design for maintenance（7）Pave only when ready（8）Build from the bottom up（9）Protect your investment（10）Keep good records1．Get water away from the roadWe can’t overemphasize the importance of good drainage.Engineers estimate that at least 90% of a road’s problems can be related to excess water or to poor waterdrainage. Too much water in any layer of a road’sstructure can weaken that la yer, leading to failure.In the surface layer, water can cause cracks and potholes. In lower layers it undermines support, causing cracks and potholes. A common sign of water in an asphalt road surface is alligator cracking — an interconnected pattern of cracks forming small irregular shaped pieces that look like alligator skin. Edge cracking, frost heaves, and spring breakup of pavements also point to moistureproblems.To prevent these problems remember that water:• flows downhill• needs to flow somepla ce• is a problem if it is not flowingEffective drainage systems divert, drain and dispose of water. To do this they use interceptor ditches and slopes,road crowns, and ditch and culvert systems.Divert —Interceptor ditches, located between the road and higher ground along the road, keep the water from reaching the roadway. These ditches must slope so they carry water away from the road.Drain —Creating a crown in the road so it is higher along the centerline than at the edges encourages water to flow off the road. Typically a paved crown should be 1⁄4" higher than the shoulder for each foot of width from the centerline to the edge. For gravel surfaces the crown should be 1⁄2" higher per foot of width. For this flow path to work, the road surface must be relatively water tight. Road shoulders also must be sloped away from the road to continue carrying the flow away. Superelevations (banking) at the outside of curves will also help drainthe road surface.Dispose —A ditch and culvert system carries water away from the road structure. Ditches should be at least one foot lower than the bottom of the gravel road layer that drains the roadway. They must be kept clean and must be sloped to move water into natural drainage. If water stays in the ditches it can seep back into the road structure and undermine its strength. Ditches should also be protected from erosion by planting grass, or installing rock and other erosion control measures. Erosion can damage shoulders and ditches, clog culverts, undermine roadbeds, and contaminate nearby streams and lakes. Evaluate your ditch and culvert system twice a year to ensure that it works. In the fall, clean out leaves and branches that can block flow. In spring, check for and remove silts from plowing and any dead plant material left from the fall.2．Build on a firm foundationA road is only as good as its foundation. A highway wears out from the top down but falls apart from the bottom. The road base must carry the entire structure and the traffic that uses it.To make a firm foundation you may need to stabilize the roadbed with chemical stabilizers, large stone called breaker run, or geotextile fabric. When you run into conditions where you suspect that the native soil is unstable, work with an engineer to investigate the situation and design an appropriate solution.3．Use the best materialsWith all road materials you “pay now or pay later.” Inferior materials may require extensive maintenance throughout the road’s life. They may also force you to replace the road prematurely.Crushed aggregate is the best material for the base course. The sharp angles of thecrushed material interlock when they are compacted. This supports the pavement and traffic by transmitting the load from particle to particle. By contrast, rounded particles act like ballbearings, moving under loads.Angular particles are more stable than rounded particles.Asphalt and concrete pavement materials must be of the highest quality, designed for the conditions, obtained from established firms, and tested to ensure it meets specifications.4．Compact all layersIn general, the more densely a material is compacted, the stronger it is. Compaction also shrinks or eliminates open spaces (voids) between particles. This means that less water can enter the structure. Water in soil can weaken the structure or lead to frost heaves. This is especially important for unsurfaced (gravel) roads. Use gravel which has a mix of sizes (well-graded aggregate) so smaller particles can fill the voids between larger ones. Goodcompaction of asphalt pavement lengthens its life.5．Design for traffic loads and volumesDesign for the highest anticipated load the road will carry. A road that has been designed only for cars will not stand up to trucks. One truck with 9 tons on a single rear axle does as much damage to a road as nearly 10,000 cars.Rural roads may carry log trucks, milk trucks, fire department pumper trucks, or construction equipment. If you don’t know what specific loads the road will carry, a good rule of thumb is to design for the largest piece of highway maintenance equipment that will be used on the road.A well-constructed and maintained asphalt road should last 20 years without major repairs or reconstruction. In designing a road, use traffic counts that project numbers and sizes of vehicles 20 years into the future. These are only projections, at best, but they will allow you to plan for traffic loadings through a road’s life.6．Design for maintenanceWithout maintenance a road will rapidly deteriorate and fail. Design your roads so they can be easily maintained. This means:• adequate ditches that can be cleaned regularly• culverts that are marked for easy locating in the spring• enough space for snow after it is plowed off the road• proper cross slopes for safet y, maintenance and to avoid snow drifts• roadsides that are planted or treated to prevent erosion• roadsides that can be mowed safelyA rule of thumb for adequate road width is to make it wide enough for a snowplow to pass another vehicle without leaving the travelled way.Mark culverts with a post so they can be located easily.7．Pave only when readyIt is not necessary to pave all your roads immediately. There is nothing wrong with a well-built and wellmaintained gravel road if traffic loads and volume do not require a paved surface. Three hundred vehicles per day is the recommended minimum to justify paving.Don’t assume that laying down asphalt will fix a gravel road that is failing. Before you pave, make sure you have an adequate crushed stone base that drains well and is properly compacted. The recommended minimum depth of crushed stone base is 10" depending on subgrade soils. A road paved only when it is ready will far outperform one that is constructed too quickly.8．Ê Build from the bottom upThis commandment may seem obvious, but it means that you shouldn’t top dress or resurface a road if the problem is in an underlying layer. Before you do any road improvement, locate the cause of any surface problems. Choose an improvement technique that will address the problem. This may mean recycling or removing all road materials down to the native soil and rebuilding everything. Doing any work that doesn’t solve the problem is a waste of money and effort.9．Ê Protect your investmentThe road system can be your municipality’s biggest investment. Just as a home needs painting or a new roof, a road must be maintained. Wisconsin’s severe climate requires more road maintenance than in milder places. Do these important maintenance activities: Surface —grade, shape, patch, seal cracks, control dust, remove snow and iceDrainage —clean and repair ditches and culverts; remove all excess materialRoadside —cut brush, trim trees and roadside plantings, control erosionTraffic service —clean and repair or replace signsDesign roads with adequate ditches so they can be maintained with a motor grader. Clean and grade ditches to maintain proper pitch and peak efficiency. After grading, remove all excess material from the shoulder.10．Keep good recordsYour maintenance will be more efficient with good records. Knowing the road’s construction, life, and repair history makes it much easier to plan and budget its future repairs. Records can also help you evaluate the effectiveness of the repair methods and materials you used.Good record keeping starts with an inventory of the system. It should include the history and surface condition of the roadway, identify and evaluate culverts and bridges, note ditch conditions, shoulders, signs, and such structures as retaining walls and guardrails.Update your inventory each year or when you repair or change a road section. A formal pavement management system can help use these records and plan and budget road improvements.ResourcesThe Basics of a Good Road#17649, UW-Madison, 15 min. videotape. Presents the Ten Commandments of a Good Road. Videotapes are loaned free through County Extension offices.Asphalt PASER Manual(39 pp), Concrete PASER Manual (48 pp), Gravel PASER Manual (32 pp). These booklets contain extensive photos and descriptions of road surfacesto help you understand types of distress conditions and their causes. A simple procedure for rating the condition helps you manage your pavements and plan repairs.Roadware, a computer program which stores and reports pavement condition information. Developed by the Transportation Information Center and enhanced by the Wisconsin Department of Transportation, it uses the PASER rating system to provide five-year cost budgets and roadway repair/reconstruction priority lists.Wisconsin Transportation Bulletin factsheets, available from the Transportation Information Center (T.I.C.).Road Drainage, No. 4. Describes drainage for roadways, shoulders, ditches, and culverts.Gravel Roads, No. 5. Discusses the characteristics of a gravel road and how to maintain one.Using Salt and Sand for Winter Road Maintenance,No. 6. Basic information and practical tips on how to use de-icing chemicals and sand.Culverts—Proper Use and Installation, No. 15. Selecting and sizing culverts, designing, installing and maintaining them.Geotextiles in Road Construction/Maintenance andErosion Control, No. 16. Definitions and common applications of geotextiles on roadways and for erosion control.T.I.C. workshops are offered at locations around the state.Crossroads,an 8-page quarterly newsletter published by the T.I.C. carries helpful articles, workshop information, and resource lists. For more information on any of these materials, contact the T.I.C. at 800/442-4615.中文译文一个良好的公路的基础长久以来我们已经掌握了如何铺设好一条道路的方法，考古学家发现在4600年古埃及使用建造金字塔的石块铺设道路，后来，罗马人使用同样的方法建立了一个庞大的道路系统，这种方法一直沿用到今天。
二级公路设计毕业设计(论文)-二级公路毕业设计
二级公路设计毕业设计(论文)-二级公路毕业设计第一章绪论1.1 绪言1.1.1 选题的意义交通运输事业具有重要的意义，对国家而言，促进了文化交流，促进了国家、社会的团结与统一，对国防和军事具有重要作用。
对于社会而言，为社会提供了大量的就业机会，促进了旅游业发展，是国民经济命脉。
公路交通是衡量一个国家经济实力和现代化水平的重要标志，是国民经济发展、社会发展和人民生活必不可少公共基础设施。
公路建设的发展速度对于促进国民经济的发展，拉动其他产业的发展具有非常重要意义。
本次设计的公路是江苏常州市至江苏无锡市二级公路。
该公路地处平原，土壤肥沃，雨水充足，有较多鱼塘。
该地区长期处于交通不良状态，随着地区经济的快速发展，地区原有公路线路已经严重限制了该地区与外界经济的联系，影响了地区人民的经济生活水平的提高。
本公路的建设将大大加强地区与地区之间，地区与外界之间的联系，解决道路通行能力低的问题，促进该地区调整产业结构，常州到无锡这条二级公路是连接两地的主要交通运输通道，加强了两地在经济合作和资源互补之间的联系与沟通，改善运输条件和投资环境使丰富的资源得到开发利用，把蕴藏的土地、渔业等资源优势转化为经济优势对两地的经济发展用极其重要的意义。
1.1.2 现状与发展规划世界上无论是发达国家还是发展中国家，对水泥混凝土路面建造技术都一直在进行研究和总结，使得水泥混凝土路面在技术上日勤完善。
经济上显出一定的优势，并得到较大范围的应用。
特别是在高等级中交通的道路上，水泥混凝土路面有了较快的发展。
例如，美国在全国公路网的建设和完善中，对于交通繁忙、汽车载重量较大或增大的道路，更多的选自建造水泥混凝土路面。
国际上各国在发展水泥混凝土路面技术上的一个重要特征是密切集合本国实际和资源约束条件，起直接影响因素是本国水泥和沥青资源供给和价格情况，美国是典型的黑白两种路面几乎均等”“黑白并举”的国家。
其原因除了能源的考虑外，其经济对比分析是建立在建设、维修，养护全部建设和运营的总费用最省的价值工程基础上，强调在路面使用年限内，每平方每年的价格最节省、投资效益最高。
二级公路外文原文PDF格式的及三千字翻译
- Journal of Information Technology in Construction - ISSN 1874-4753 AUTOMATING ROAD CONSTRUCTION PLANNING WITH A SPECIFIC-DOMAIN SIMULATION SYSTEMPUBLISHED: August 2009 at /2009/36EDITOR: Amor RNashwan DawoodProfessor, Centre for Construction Innovation and Research, School of Science & Technology, University of Teesside, Middlesbrough, TS1 3BAn.n.dawood@Serafim CastroCentre for Construction Innovation and Research, School of Science & Technology, University of Teesside, Middlesbrough, TS1 3BASUMMARY:Road construction projects are very expensive, unpredictable and highly influenced by unpredictable factors, like weather, type of soil, environmental issues, and other factors. This has led to difficulties in developing accurate construction plans and modelling the construction operation using a traditional simulation system. In this context, the aim of this research is to create a knowledge driven road construction simulation system to assist project managers in generating accurate and reliable road construction plans.Road construction operations and rules governing the actions and interactions of the resources have been identified, developed, classified and modelled through a comprehensive analysis of 145 road construction projects. For every road construction operation (activity) a computer-based template for atomic models was defined and developed. The models encapsulate productivity equations and factors influencing the productivity of resources and automating the scheduling of works. Also, the models provide a means for evaluating several resource allocation alternatives under a wide range of scenarios.A real life case study was modelled to identify applicability, accuracy and usefulness of the developed simulation system and results are presented in this paper. The study concluded that the system generated fast and accurate productivity and unit cost of road activities to develop a construction schedule of the road construction project. KEYWORDS: Simulation, Road construction, Knowledge base, Productivity, Case studyREFERENCE:Dawood N, Castro S (2009) Automating road construction planning with a specific-domain simulation system, Journal of Information Technology in Construction (ITcon), Vol. 14, pg. 556-573, /2009/36COPYRIGHT: © 2009 The authors. This is an open access article distributed under the terms of the Creative Commons Attribution 3.0 unported (/licenses/by/3.0/), whichpermits unrestricted use, distribution, and reproduction in any medium, provided theoriginal work is properly cited.1. INTRODUCTIONCurrent practices in the road construction industry suggested that planning and scheduling in road construction is inefficient and projects are often over budget and over time (Castro et al, 2005). Also, project managers use only their experiences, historical and technical data and gut feeling to plan and manage the process. In order to have efficiency gains and construct projects on time and on budget, more innovative tools and techniques are needed to assist managers in planning and managing road construction projects. Also, there is a need for tools that will be able to assist project managers to study and compare all possible strategies and methodologies for the execution of the works and without this comparison there is will be no evidence that the planner’s choice corresponds to the most advantageous possibility.The idea that innovation in construction should go beyond the boundaries of the products and construction processes and reach the organisational structure, management techniques and business models of the construction companies (Hitt et al, 2001) is commonly accepted as being correct. However and despite all the potential benefits and value offered by innovative management techniques, various researchers have concluded that systems related to the planning of construction projects and using simulation modelling and visualisation, have had a limited penetration in the construction industry (Kamat and Martinez, 2001; Hajar and AbouRizk, 2001). Researchers have also concluded that the major drawbacks for the use of simulation systems in construction planning are the fact that (i) most of the IT or other innovative solutions have not been tailored to fit the project manager’s requirements (Gann and Salter, 2000); (ii) the long-term expectation requirements for the IT tools are in conflict with the traditional short-term project based assessment of the results in the industry (Pries and Janszen, 1995) and (iii) the investment required for the acquisition of the systems is high, the learning effort and time to build the simulation models are considerable (AbouRizk and Mather, 2000).The fact that most of the simulation systems are implementations of the concept of the CYCLONE system developed by (Halpin, 1973) are general purpose and mostly network based, may be the explanation for the limited penetration of simulation in construction planning. RISim, a general-purpose simulation system (Chau and Li, 2001), considers construction resources as objects and the interactions between resources as the operation logic. There are two abstraction levels in RISim: one referring to the resource level and the second to the process level. The resource level deals with resources and their relationship, while the process level deals with construction activities. Logic is associated to each process (activity) to describe the actions taken in the construction process. KMOS (Kim and Gibson, 2002) was presented as interactive simulation modelling oriented for heavy construction operations. The system shares both resource and process-oriented characteristics. The system allows for modularised simulation model building and provides step-by-step guidance in model building.AbouRizk and Mather, (2000) developed a simulation system through integration with 3D CAD in which each resource is associated with its “atomic model”. The concept of “atomic model” has been presented by Ziegler (1987), Luna (1992) and Odeh (1992) in order to simplify simulation model building.In all the mentioned simulation systems the model should be built every time the simulation is required and this may be tedious and time-consuming. Moreover, the general-purpose characteristics of those systems reduce their simplicity and applicability. Also, these simulation models are ‘number crunching’ machines and lack ‘intelligence’ which can be essential if a practical real life situation is to be modelled. Other simulation systems include visualisation of the construction process, i.e. provide visual understanding of the construction process, either in terms of the physical aspect or in terms of the sequence of execution (Op Bosch, 1994). In these types of systems can be included a methodology proposed by (McKinney and Fischer, 1998) for the generation, evaluation and visualisation of construction schedules using a 4D CAD. VIRCON is another 4D modelling system allowing the elaboration of the tradeoffs between the sequencing of the works and respective spatial distribution (Dawood et al, 2004 and Winch, 2002).One of the major conclusions that the authors have reached in reviewing historical and recent literature is that there is very little work that has been undertaken in the simulation of road construction. No paper was found dealing with road construction as a whole process, composed by tasks defined as “plan the project”, “execute the works” and “evaluate the economic results”. The difficulty faced by the researchers is probably due to the fact that road construction is difficult to model and simulate and has a particular culture for planning and performance management. This has been influenced by the following distinct road construction risk factors: •The geographical extension of the works;•The sensitivity of the road works to the local conditions (materials to be removed, water table, site organisation, accesses, etc.);•The sensitivity of road works to the weather conditions;•The environmental impacts;•The potential conflicts with other social and economic activitiesTo overcome issues associated with previous research models and introduce simplicity, knowledge and specificity into a simulation system, this paper discusses a modular approach that was implemented using integration of common MS Windows commercial software packages like spreadsheets, databases and MS Project. The proposed simulation system dubbed “RoadSim” is based on a modular approach known as the “atomic model” introduced by (Ziegler, 1987) and used by (Luna, 1992) and (Odeh, 1992). The main principle of the atomic model depends on the possibility to break down a complex system like road construction into several sub systems of lesser complexity. The final sub system is a module or atomic model. For example, an atomic model of a tipper truck can be used in all activities that include “loading and hauling”, such as cut to fill,cut to spoil, sub base execution; bituminous mixes production and placing. The following section details the principles of ‘RoadSim’ and development processes.2. ROADSIM PRINCIPLESRoad construction is basically an equipment-intensive process and therefore is ideal for simulation since the activity of an equipment unit is repetitive and can be considered as partially self-controlled and influenced only by the respective working conditions (Castro and Dawood, 2005).The main principle that underpins the concept of RoadSim was the possibility to break down a complex system like road construction into several sub-systems of lesser complexity. The process of division continues until the simplest indivisible entity is found. This final sub-system is a module or atomic model, as shown in Figure 1.A complex construction operation is the aggregation of very small modules or atomic models. Once these atomic models are developed, any construction operation can be modelled by coupling the “atoms” that constitute the “substance”. For example, the process of the tipper truck activity shown in Figure 2 is always the same, the differences being the results of the interactions with other resources working in the same activity (type of loader, number of trucks, etc.) and the interactions with the actual working conditions like technical specifications, hauling distances, type of access, availability of space for manoeuvring, etc.Indicates idle state of tipper truckNormal working state of tipper truckFIG. 2: Atomic model of Tipper Truck for loading and hauling activity.For the tipper truck, several events can be identified as indicated in Table 1. In this example, it can be seen that the modelling can be done by tracking certain variables such as, time elapsed, state of the system at the time “t”, etc. Table 1 refers to the action of a single resource and is the lowest level of the action of the tipper truck. Hence the term atomic model describes the process involved.TABLE 1: Events in tipper truck activityTime T1 T2 T3 T4 T5 T6 T7Event Arrival Loading TravelloadedManoeuvre Dumping Travel empty QueuingTheoretically it is possible to continue breaking the action of the tipper truck into smaller parcels like “manoeuvring” or “dumping” (that can be considered the “electrons” and “neutrons” of the atom). However, this might not be useful in the practical real world, though that reasoning may be used for the definition of the cycle time. In the case of the tipper truck action, the cycle time will be always the result of the aggregation of the times of all parcels (“electrons”) that compose the atomic model (time of “loading”, time of “dumping”, time of “hauling loaded”, etc.).If more than one resource is involved in a concurrent action, the process can also be modelled in the same way, as occurs with the modelling of the pay loader and tipper truck indicated in Table 2.TABLE 2: Loading operation modellingTime T11 T21 T31 T41 T51 T61 T71Loader Events Travelfrontward(A) LoadbucketTravelbackward(A)Manoeuvre Travelfrontward(B)LoadtruckTravelbackward(B)Time T12 T22 T32 T42 T52 T62 T72 T82 Truck Events Arrival Start load End load Travel loaded Manoeuvre Dump Return QueuingTipper truck routineWhereas A indicates operation at loading place and B indicates at dumping or spoiling sitesTable 2 contains two atomic models, pertaining to the tipper truck and pay loader, respectively. The modelling of the combination of the two resources cannot be the simple addition of the two atomic models since Table 2 does not depict the problems that may arise with the interactions of the resources. To show the interactions properly, a flowchart is required. Figure 3 shows a flowchart referring to the combined actions of the tipper truck and pay loader and problems related with queues can be highlighted in the flow chart. The actual performance of combining atomic models will be influenced by a wide range of risk factors which influence productivity and cost. This paper develops an empirical approach backed by knowledge generated from analysis and knowledge elicitation of historical projects to assess the impact of a wide range of risk factors and encapsulate this in ‘RoadSim’ as given in the following example.FIG. 3: Tipper truck/loader activity flow chart.As an example, the performance of the activity of the tipper truck depicted in Figure 2 is a result of the integration of the inherent characteristics of the machine (power engine, bucket capacity, etc.) with the interactions introduced into the construction process by the working conditions. But the tipper truck always performs the same sequence of actions: loads, travels loaded, dumps and returns to the loading point. That is the atomic model. The differentiation will be introduced by the actual working conditions: type of access, hauling distance, type of material loaded, number of trucks in the operation, availability of space at the dumping area, size of the loader, skill of the driver, site organisation, etc.Therefore, the action of a resource can be defined as given in Eq. (1)A = A m * W c ------------------------------------------- (1) In which,A = Productivity of an active task;A m = Atomic model (basic productivity of an activity);W c = Factor referring to working conditions.As the atomic model is immutable for a given resource, the A m can be used in different construction activities. For example, the atomic model of a tipper truck can be used in all activities including “loading and hauling”, such as cut to fill, cut to spoil, stone base or sub-base execution, bituminous mixes production and placing, chemically stabilised layers, etc.In this way, the atomic model can be seen as a “module” capable of being used in different activities or construction operations. This modularity leads to the establishment of a concept that can be presented by Eq. (2) A T = ∑ (A mi * W ci) ----------------------------------- (2) In whichA T = Total productivity of a given activityA mi = Atomic models of the resources intervening in the activity (productivity);W ci = Working conditions influencing each resource action.Using the defined concept, the modelling of an activity is always performed through following steps:a.Definition of the resources that will be used in the execution of the different tasks composing theactivity;b.Definition of the atomic models of every resources used;c.Definition of the working conditions affecting the performance of each resource;d.Coupling of the atomic models that are already affected by the working conditions.In the case of RoadSim these parameters have been defined through a knowledge acquisition process which is given in the following section.3. KNOWLEDGE ACQUISITION PROCESSThe identification and definition of the influence of the working conditions on performance of a resource or construction system can only be achieved through a detailed analysis of the outcomes of real life road construction projects carried out previously. The influence of the working conditions are risk factors that practitioners have responded to by establishing practical and judgemental rules to take into account the respective consequences. In order to obtain the expert rules concerning road construction, a knowledge acquisition process was undertaken, aimed at the identification of activities and resources included in road construction projects, alternative construction methods as well as the influence of the working conditions on the performance of such resources. In order to achieve this, 145 previous road construction projects in Portugal have been analysed thoroughly. The value of each project varies from 8 to 53 million Euros. For the definition of the activities that constitute "a typical road project" the authors analysed the Bill of Quantity (BOQ) of all projects. The activities have been grouped into three categories "earthworks", "drainage" and "pavement" and the activities that have a frequency of more than 50% in all BOQ for the 145 projects were included in the analyses. Alongside historical information, the authors used equipment and machinery manufacturers’ information for the definition of the equipment used in road construction, respective productivity and determination of the effect of the working conditions. The first step in the construction site knowledge acquisition process was the definition and analyses of construction activities, basic package of equipment units, materials and labour. Also, the analyses yield the definition of the rules governing the actions and interactions between resources and working conditions in road construction.In the second step, 50 basic road construction activities were identified and the respective alternative methods of construction were identified. A list of the activities will be shown in the case study. As an example, Table 3 shows the different methods of performing earthworks, corresponding basically to using different combinationsof equipment units to execute the works. Note that independently of the size or objective of the road, earthworks in road construction are always an association / aggregation of the following activities:(Cut + hauling + dump + levelling + watering + compaction)The same exercise was performed for other identified activities.TABLE 3: Earthworks activities and corresponding tasksActivity Execution Method Tasks (by resources)Method 1 Dozing + pay loaderCutMethod 2 ExcavatorMethod 3 Pusher + motor scraperMethod 1 Tipper truckHaul / dumpMethod 2 DumperMethod 3 Motor scraperLevellingMethod 1 Motor graderMethod 2 Bulldozer (mass earthworks)Watering Water tankerMethod 1 Vibrating rollerCompactionMethod 2 Sheep foot rollerMethod 3 Pneumatic rollerThe determination of the productivities of the atomic models considered necessary for the modelling of the totality of the road construction domain was obtained from the analysis of historical data of 145 projects that were constructed in Portugal. This productivity data was then grouped according to the conditions under which projects were constructed. In this case, parameters referring to the working conditions have been established and linked to productivities of atomic models, namely those concerned with the “site organisation”, “job efficiency”, “type of accesses”, “queue effect”, “random works”, etc.By capturing professional knowledge, historical records and manufacturer’s information, a basic package of equipment used in road construction was defined, taking advantage of the fact that manufacturers tend to produce similar types (capacity and functioning) of equipment units. For the identified units it was observed that some associations of equipment could be defined, meaning that some types are “forced” to work in a sort of partnership with others. For example, a motor scraper never interacts with a tipper truck, since the scraper has been designed to work and interact with a bulldozer (pusher) at the loading point and with a bulldozer or motor grader at the dumping point. The possible associations are shown in Table 4. The identification of these associations is important since it allows the study of possible interactions between different equipment partners and their related capacities.TABLE 4: Association of equipment resources in road constructionRESOURCE EQUIPMENT PARTNERBulldozer Pay loaderMotor graderRollerMotor scraper BulldozerMotor graderPay Loader BulldozerTipper truckDumperExcavator Tipper TruckDumperMotor Grader Tipper truckDumperMotor scraperRollerWater tankerTipper truck ExcavatorPay loaderAsphalt plantConcrete plantCraneMotor graderAsphalt paverSlip form paverDumper Motor graderExcavatorPay loaderWith regards to the working conditions and interactions, the same reasoning and procedures were adopted in order to obtain the identification and definition of the influence of the respective factors. Numerical coefficients have been attributed to each factor, therefore allowing the determination of the real productivity of the resources performing an activity in the following equation:P = P b * w1* w2 * w3-------------------------- (3)In which,P = Real productivity of the considered resource – m3/hr;P b = Productivity of the atomic model – m3/hr;W1 = Factor referring to the working conditions;W2 = Parameter referring to the interactions with the “partner” resource;W3 = Parameter related with the random works of possible execution during the construction process. With this information, empirical equations have been defined for the determination of the productivities of every resource in a given activity. Eventually, all of the processes were summarised graphically as the example shown in Figure 4, which represents the actions and interactions of a motor scraper and bulldozer in the push and load task.Hundreds of productivity empirical equations, an example shown in Figure 4 have been developed and used to populate a database that is the core infrastructure of the simulation system. Figure 4 will be further elaborated in section 5.4. IMPLEMENTING A ROAD CONSTRUCTION-ORIENTED SIMULATION SYSTEMRoadSim has been developed to mimic the way in which road construction planners develop construction plans. The main processes of RoadSim are: determination of near optimum cost and time of road activities, identification of the most productive resource combinations and production of a schedule that meets the clients and company requirements. The main inputs to RoadSim are: bill of quantities, technical specification of resources and working conditions.The simulation system was implemented using the architecture shown in Figure 5. At the heart of the system is a relational database which holds productivities of different resource combinations and information about previous projects which include activities, resource attributes and productivity factors. The database contains all atomicmodels and modules for modelling the most common road construction operations. The coupling of these atomic models is performed automatically by the system.FIG. 5: RoadSim system architectureFIG. 6: RoadSim software process flowchartThe system was designed to allow updating and customisation to the specific situation of the user. For example adding more resources, updating formula to conform to specific conditions of risk factors (weather, type of soil, terrain conditions etc). Figure 6 shows the flow chart of the model. The flow chart is self explanatory and the main processes are:•Selecting road activities of a new project from a database which includes standard naming of activity and quantities. Table 5 shows a case study example of BOQ which include activities, unitsand quantities. The example given will be discussed further in the case study section.•Develop alternatives for each activity in terms of time and cost under different conditions and resource allocations. As given in Table 3, for each activity there might be a number of constructionmethods and different combinations of resources. This was identified from knowledge elicitationof previous projects discussed earlier in this paper. To calculate productivity, users input the actualworking conditions affecting every atomic model. For example and referring to the excavator, theuser should input:o Type of excavator: the menu offers 4 options and the planner should select the typethat is going to be used in the project;o Rotation angle: according to the site conditions, the menu offers a wide range of possible angles between the excavator and the truck being loaded;o % Cut Height: the excavations level corresponds to a certain percentage of the optimum height of cut of the selected excavator;o Material: the type of material to be processed using geotechnical or site information; o Mat Condition: refers to the expected difficulty in cutting the material, which ranges from "soft" to "very hard";oKey: refers to the site organisation (job efficiency) which can be from "poor" to "excellent" and Phi: refers to the material characteristics.;•Selection of an option which can be achieved by a project manager and based on the condition of the project. For example a project manager might select an expensive option at low risk by deploying certain resources that can work under severe weather conditions.• Record information in the database, establish dependences of activities and view information in MS-Project.•To reduce the development cost, minimise the learning process and reduce the implementation cost, the system was designed and implemented using MS Excel, MS Access, AutoCAD, MS Project and VBA.TABLE 5: Shows the type of equipments used and site condition factor affecting the productivity of the activityVegetation (µ) Type of Equipment (Bulldozer)BucketCapacity (Bc) – m3Cycle time (Ct)- minVery denseDenseMedium densityWeak density Clearing Depth (e) Ttta 3.9 0.33 + 0.035*D 0.125 Tttb 5.6 0.33 + 0.037*D 0.175 Tttc 11 0.33 + 0.035*D 0.200 Tttd 16.40.33 + 0.034*D0.700.600.550.500.225Good Average Rather(below average) Poor Working Condition/ Job efficiency (Ke)0.830.750.670.58In RoadSim, certain ‘subjective’ variables are quantified through a judgemental decision based on professional experience on site. The project planners or construction managers will decide the selection of particular variables that really affect productivity of road activities.5. CASE STUDYRoadSim is a distinctive simulation model in comparison with previous developments of simulation models. It focuses on calculation of productivity and unit cost under different resource levels and site conditions for linear construction projects and in particularly in road construction. RoadSim is developed for master scheduling at pre-construction and bidding stages to analyse the total duration and cost of road construction activities. The RoadSim model provides an ideal solution for productivity and unit cost of road activities by selecting ideal equipment sets under different site conditions to maximise the productivity. A detailed case study is presented to validate the developed RoadSim simulation model as follows:A case study is presented referring to the tests carried out using real life road construction projects. The case study uses a section of the A25, a road project constructed in Portugal between the year 2003 and 2005, see Figure 7. The section selected constituted Lot 2, between “Talhadas” and “Vouzela” and has a length of 17.085 km. The contractor established a new quarry in the area and installed a 200 ton asphalt plant.。
二级公路毕业设计论文
二级公路毕业设计论文
题目：二级公路设计与规划
摘要：
本论文以二级公路的设计与规划为研究对象，分析了现代交通发展趋势和目前二级公路运营状况，并结合实地调研，提出了一套完整的二级公路设计与规划方案。
通过对现有交通情况和既有二级公路设施的评估，指出了改善当前道路状况的必要性，并采取合适的设计和规划策略，提出了二级公路设计与规划的几项重要原则和步骤。
最后，通过实例分析，验证了所提方案的可行性和实用性，为二级公路的设计与规划提供了一定的借鉴和参考价值。
关键词：交通规划；二级公路；设计原则；规划步骤
1.引言
随着社会经济的快速发展，交通运输成为了推动经济增长和社会发展的重要因素。
二级公路作为连接城市和农村，促进地区交通流通的重要干线，具有不可替代的作用。
然而，由于各种原因，目前二级公路发展不平衡，存在一系列问题亟需解决。
本论文旨在研究现代交通发展趋势，分析二级公路的运营状况，提出一套完整的二级公路设计与规划方案，以期改善现有道路状况，提高交通效率。
2.现代交通发展趋势与二级公路运营状况
2.1现代交通发展趋势
2.2二级公路运营状况的问题
3.二级公路设计与规划的原则和步骤
3.1设计原则
3.2设计步骤
4.二级公路设计与规划实例分析4.1实例背景
4.2设计与规划方案分析
4.3结果与讨论
5.结论与展望。
公路路面毕业论文中英文资料外文翻译文献
公路路面中英文资料外文翻译文献PavementHighway pavements are divided into two main categories: rigitand flexible.The wearing surfaceof a rigid pavement is usually constructed of Portland cement concrete such that it acts like a beam over any irregularities in the underlying supporting material.The wearing surface of flexible pavements, on the other hand, is usually constructed of bituminous material such that they remain in contact with the underlying material even when minor irregularities occur.Flexible pavements usually consist of a bituminous surface underlaid with a layer of granular material and a layer of a suitable mixture of coarse and fine materials.Coarse aggregatesFine aggregatesTraffic loads are transferred by the wearing surface to the underlying supporting materials through the interlocking of aggregates, the frictionaleffect of the granular materials, and the cohesion of the fine materials.Flexible pavements are further divided into three subgroups: high type, intermediate type, and low type. High-type pavements have wearing surfaces that adequately support the expected traffic load without visible distress due to fatigue and are not susceptible to weather conditions.Intermediate-type pavements have wearing surfaces that range from surface treated to those with qualities just below that of high-type pavements. Low-type pavements are used mainly for low-cost roads and have wearing surfaces that range from untreated to loose natural materials to surface-treated earth.The components of a flexible pavement include the subgradeor preparedroadbed, the subbase, basecourse, and the surface course (Fig.11.1).✹Upper surface courseMiddle surface courseLower surface courseThe performance of the pavement depends on the satisfactory performance of each component, which requires proper evaluation of the properties of each component separately.✹The subgrade is usually the natural material located along the horizontal alignment of the pavement and serves as the foundation of the pavement structure.✹The subgrademay also consist of a layer of selected borrow materials, well compacted to prescribedspecifications.✹Compacting plantCompaction deviceCompactnessIt may be necessary to treat the subgrade material to achieve certain strength properties required for the type of pavement being constructed.Located immediately above the subgrade, the subbase component consists of a superior quality to that which generally is used for subgrade construction. The requirements for subbase materials are usually given in terms of the gradation, plastic characteristics, and strength. When the quality of the subgrade material meets the requirements of the subbase material, the subbase component may be omitted.In cases where suitable subbase material is not readily available ,the available material can be treated with other materials to achieve the necessary properties. This process of treating soils to improve their engineering properties is know as stabilization.✹The base course lies immediately above the subbase. It is placed immediately above the subgrade if a subbase course is not used.✹This course usually consists of granular materials such as crushed stone, crushed or uncrushed.The specifications for base course materials usually include stricter requirements than those for subbase materials, particularly with respect to their plasticity, gradation, and strength.Materials that do not have the required properties can be used as base materials if they are properly stabilized with Portland cement, asphalt, or lime .In some cases, high-quality base course materials may also be treated with asphalt or Portland cement to improve the stiffness characteristics of heavy-duty pavementsThe surface course is the upper course of the road pavement and is constructed immediately above the base course. The surface course in flexible pavement usually consists of a mixture of mineral aggregates and asphaltic materials.It should be capable of withstanding high tire pressures, resisting the abrasive forces due to traffic, providing a skid-resistant driving surface, and preventing thepenetration of surface water into the underlying layers.✹The thickness of the wearing surface can vary from 3 in. to more than 6 in.（inch，英寸，2.54cm）, depending on the expected traffic on the pavement.It was shown that the quality of the surface course of a flexible pavement depends on the mix design of the asphalt concrete used.✹Rigid highway pavements usually are constructed to carry heavy traffic loads, although they have been used for residential and local roads. Properly designed and constructed rigid pavements have long service lives and usually are less expensive to maintain than the flexible pavements.✹The Portland cement concrete commonly used for rigid pavements consists of Portland cement, coarse aggregate, fine aggregate, and water. Steel reinforcing rods may or may not be used, depending on the type of pavement being constructed.Rigid highway pavements be divided into three general type: plain concrete pavements, simply reinforced concrete pavements, and continuously reinforced concrete pavement. The definition of each pavement type is related to the amount of reinforcement used.Plain concrete pavement has no temperature steel or dowels for load transfer. However, steel tie bars are often used to provide a hingeeffect at longitudinal joints and to prevent the opening of these joints. Plain concrete pavements are used mainly on low-volume highways or when cement-stabilized soils are used as subbase.✹Joints are placed at relatively shorter distances (10 to 20 ft) than with the other types of concrete pavements to reduce the amount of cracking.In some case, the transverse joints of plain concrete pavements are skewed about 4 to 5 ft in plan, such that only one wheel of a vehicle passes through the joint at a time. This helps to provide a smoother ride.Simply reinforced concrete pavements have dowels for the transfer of traffic loads across joints, with these joints spaced at larger distances, ranging from 30 to 100 ft. Temperature steel is used throughout the slab, with the amount dependent on the length of the slab. Tie bars are also commonly used in longitudinal joints.h/2 h/25~10cm 填缝料横向施工缝构造Continuously reinforced concrete pavements have no transverse joints, except construction joints or expansion joints when they are necessary at specific positions, such as at bridges.These pavements have a relatively high percentage of steel, with the minimum usually at 0.6 percent of the cross section of the slab. They also contain tie bars across the longitudinal joints.Bituminous Surface CoursesThe bituminous surface course has to provide resistance to the effects of repeated loading by tyres and to the effects of the environment.✹ In addition, it must offer adequate skid resistance in wet weather as well ascomfortable vehicle ride. It must also be resistant to rutting and to cracking.✹ It is also desirable that surface course is impermeable, except in the case ofporous asphalt.Hot rolled asphalt (HRA) is a gapgraded material with less coarse aggregate. In fact it is essentially a bitumen/fine aggregate/filler mortar into which some coarse aggregate is placed.The mechanical propertiesare dominated by those of the mortar. This material has been extensively used as the wearing course on major road in the UK, though its use has recently declined as new materials have been introduced.✹ It provides a durablelayer with good resistance to cracking and one which isrelatively easy to compact. The coarse aggregate content is low (typically 30%) which results in the compacted mixture having a smooth surface. Accordingly, the skid resistance is inadequate and precoated chippings are rolled into the surface at the time of laying to correct this deficiency.In Scotland, HRA wearing course remains the preferred wearing course on trunk roads including motorway but ， since 1999 thin surfacings have been the preferred option in England and Wales. Since 1999 in Northern Ireland, HRA wearing course and thin surfacings are the preferred permitted options.Porous asphalt (PA) is a uniformly graded material which is designed to provide平缝加拉杆型large air voids so that water can drain to the verges within the layer thickness. If the wearing course is to be effective, the basecourse below must be waterproof and the PA must have the ability to retain its open textured properties with time.Thick binder films are required to resist water damage and ageing of the binder. In use, this material minimizes vehicle spray, provides a quiet ride and lower rolling resistance to traffic than dense mixtures.✹It is often specified for environmental reasons but stone mastic asphalt (SMA) and special thin surfacings are generally favoured in current UK practice.There have been high profile instances where a PA wearing course has failed early in its life. The Highways Agency does not recommend the use of a PA at traffic levels above 6000 commercial vehicles per day.✹Asphaltic concrete and dense bitumen macadam (DBM) are continuously graded mixtures similar in principle to the DBMs used in roadbases and basecourses but with smaller maximum particle sizes. Asphaltic concrete tends to have a slightlydenser grading and is used for road surfaces throughout the world with the excepting of the UK.✹It is more difficult to meet UK skid resistance Standards with DBMs than HRA, SMA or PA. This problem can be resolves by providing a separate surface treatment but doing so generally makes DBM economically unattractive.✹Stone mastic asphalt (SMA) material was pioneeredin Germany and Scandinavia and is now widely used in the UK. SMA has a coarse, aggregrate skeleton, like PA, but the voids are filled with a fine aggregate/filler /bitumen mortar.✹In mixtures using penetration grade bitumen , fibres are added to hold the bitumen within the mixture (to prevent “binder drainage”).Bitumen✹oil bitumen( earth oil)✹natural bitumen✹TarWhere a polymer modified bitumen is used, there is generally no need for fibres. SMA is a gap-graded material with good resistance to rutting and high durability. modified bitumen✹SBS✹SBR✹PE\EV A✹It differs from HRA in that the mortar is designed to just fill the voids in the coarse aggregate whereas, in HRA, coarse aggregate is introduced into the mortar and does not provide a continous stone matrix. The higher stone content HRAs ,however, are rather similar to SMA but are not wide used as wearing courses in the UK, being preferred for roadbase and basecourse construction.A variety of thin and what were called ultra thin surfacings (nowadays, the tendency is to use the term ‘thin surfacings’ for both thin and ultra thin surfacings )have been introduced in recent years, principally as a result of development work concentrated in France.These materials vary in their detailed constituents but usually have an aggregate grading similar to SMA and often incorporate a polymer modified bitumen.They may be used over a high stiffness roadbase and basecourse or used for resurfacing of existing pavements. For heavy duty pavements (i .e those designed to have a useful life of forty years), the maintenance philosophy is one of minimum lane occupancy, which only allows time for replacement of the wearing course to these ‘long life’ pavement structures. The new generation of thin s urfacings allows this to be conveniently achieved.The various generic mixture types described above can be compared with respect to their mechanical properties and durability characteristics by reference to Fig.12.1. This shows, in principle, how low stone content HRA, asphaltic concrete, SMA and PA mixtures mobilize resistance to loading by traffic.Asphaltic concrete (Fig.12.1a)) presents something of a compromise when well designed, since the dense aggregate grading can offer good resistance to the shear stresses which cause rutting, while an adequate binder content will provide reasonable resistance to the tensile stresses which cause cracking.In general, the role of the aggregate dominates. DBMs tend to have less dense gradings and properties which, therefore, tend towards good rutting resistance and away from good crack resistance.HRA (Fig.12.1b)) offers particularly good resistance to cracking through the binder rich mortar between the coarse aggregate particles. This also provides good durability but the lack of coarse aggregate content inhibits resistance to rutting.SMA and PA are shown in the same diagram ( Fig.c)) to emphasis the dominant role the coarse aggregate. In both case, well coated stone is used. In PA, the void space remains available for drainage of water, whilst in SMA, the space is occupied by a fine aggregate/ filler/ bitumen/ fibre mortar.Both materials offer good rutting resistance through the coarse aggregate content. The tensile strength of PA is low whilst that of SMA is probably adequate but little mechanical testing data have been reported to date.Drainage for Road and Airports✹Provision of adequate drainage is important factor in the location and geometric design of road and airports. Drainage facilities on any highway, street and airport should adequately provide for the flow of water away from the surface of the pavement to properly designed channels.Inadequate drainage will eventually result in serious damage to the structure.✹In addition, traffic may be slowed by accumulated water on the pavement, and accidents may occur as a result of hydroplaning and loss of visibility from splash and spray. The importance of adequate drainage is recognized in the amount of highway construction dollars allocated to drainage facilities. About25 percent of highway construction dollars are spent for erosion control anddrainage structures, such as culverts, bridges, channels, and ditches.✹Highway Drainage Structures✹One of the main concerns of the highway engineer is to provide an adequate size structure, such that the waterway opening is sufficiently large to discharge the expected flow of water.Inadequately sized structures can result in water impounding, which may lead to failure of the adjacent sections of the highway due to embankments being submerged in water for long periods.✹The two general categories of drainage structures are major and minor. Major structures are those with clear spans greater than 20 feet, whereas minor structures are those with clear spans of 20 feet or less .✹Major structures are usually large bridges, although multiple-span culverts may also be included in this class. Minor structures include small bridges and culverts.Emphasis is placed on selecting the span and vertical clearancerequirements for major structures. The bridge deck should be located above the high water mark .The clearance above the high water mark depends on whether the waterway is navigable ✹If the waterway is navigable, the clearance above the high water mark should allow the largest ship using the channel to pass underneath the bridge without colliding with the bridge deck. The clearance height, type, and spacing of piers also depend on the probability of ice jams and the extentto which floating logs and debris appear on the waterway during high water.✹An examination of the banks on either side of the waterway will indicate the location of the high water mark, since this is usually associated with signs of erosion and debris deposits. Local residents, who have lived near and observed the waterway during flood stages over a number of years, can also give reliable information on the location of the high water mark. Stream gauges that have been installed in the waterway for many years can also provide data that can be used to locate the high water mark.Minor structures, consisting of short-span bridges and culverts, are the predominant type of drainage structures on highways. Although openings for these structures are not designed to be adequate for the worst flood conditions, they should be large enough to accommodate the flow conditions that might occur during the normal life expectancy of the structure.✹Provision should also be made for preventing clogging of the structure due to floating debris and large boulders rolling from the banks of steep channels.✹Culverts are made of different materials and in different shapes. Materials used to construct culverts include concrete（reinforced and unreinforced）, corrugated steel, and corrugatedaluminum. Other materials may also be used to line the interiorof the culvert to prevent corrosion and abrasionor to reduce hydraulic resistance. For example, asphaltic concrete may be used to line corrugated metal culverts. The different shapes normally used in culvert construction include circular, rectangular (box), elliptical, pipe arch, metal box, and arch.✹The drainage problem is increased in these areas primarily for two reasons: the impervious nature of the area creates a very high runoff; and there is little room for natural water courses. It is often necessary to collect the entire storm water into a system of pipes and transmit it over considerable distances before it can be loosed again as surface runoff. This collection and transmission further increase the problem, since all of the water must be collected with virtually no pending, thus eliminating any natural storage; and through increased velocity the peak runoffs are reached more quickly.Also, the shorter times of peaks cause the system to be more sensitive to short-duration,high intensive rainfall.Storm sewers,like culverts and bridges,are designed for storms of various intensity-return-period relationships, depending uponthe economy and amount of ponding that can be tolerated.✹Airport Drainage✹The problem of providing proper drainage facilities for airports is similar in many ways to that of highways and streets. However, because of the large and relatively flat surface involved, the varying soil conditions, the absence of natural water courses and possible side ditches, and the greater concentration of discharge at the terminus of the construction area, some phases of the problem are more complex. For the average airport the over-all area to be drained is relatively large and an extensive drainage system is required. The magnitude of such a system makes it even more imperative that sound engineering principles based on all of the best available data be used to ensure the most economical design.Overdesigning of facilities results in excessive money investment with no return, and underdesigning can result in conditions hazardous to the air traffic using the airport. In order to ensure surfaces that are smooth, firm, stable, and reasonably free from flooding, it is necessary to provide a system which will do several things.It must collect and remove the surface water from the airport surfaces; intercept and remove surface water flowing toward the airport from adjacent areas; collect and remove any excessive subsurface water beneath the surface of the airport facilities and in many cases lower the ground-water table; and provide protection against erosion of the sloping areas.路面公路的路面被分为两类：刚性的和柔性的。
二级公路设计【文献综述】
毕业设计（论文）文献综述土木工程二级公路设计一、前言1、课题研究的目的本课题是某地区的一条二级公路设计，通过纸上选线、定线，考虑经济、安全、实用的因素，最终得出一个方案。
本次毕业设计也是对自居大学四年各种专业知识的综合检验，各科知识融会贯通和实践相结合。
通过它，充分理解和掌握公路设计的设计方法，步骤；熟悉各种设计规范，提高专业知识技能，掌握正确的横纵断面图的形式与画法，培养自己独立思考、动手、作图的能力，同时也为自己以后的职业生涯打下基础。
2、发展前景简介：公路运输是19世纪末随着现代汽车的诞生而产生的。
初期主要承担短途运输业务。
第一次世界大战结后，基于汽车工业的发展和公路里程的增加，公路运输走向发展的阶段，不仅是短途运输的主力，并进入长途运输的领域。
第二次世界大战结束后，公路运输发展迅速。
欧洲许多国家和美国、日本等国已建成比较发达的公路网，汽车工业又提供了雄厚的物质基础，促使公路运输在运输业中跃至主导地位。
发达国家公路运输完成的客货周转量占各种运输方式总周转量的90％左右。
随着我国现代化城市的建设和发展，人们的活动半径越来越大，对公路运输的要求也越来越高。
由于道路运输有着灵活机动，运送速度快，运输的技术简单，投资回收快的特点，公路运输也最受到欢迎。
世界各国经济发展的历史证明，道路运输是商品经济发展的催化剂。
经济发达国家，其交通运输特别是道路运输必定很发达。
因此，道路运输发展水平作为衡量和反映一个国家和一个地区经济发展水平的主要指标之一。
我国近年来由于对公路，城市道路建设的重视，高速公路的修建已经达到世界的前列。
3、设计中有关问题：⑴沿线设施各项工程的位置的合理安排；⑵环境保护的内容、措施及方案的确定；⑶确定占用土地、拆迁建筑物及电力、电讯等设施的数量；⑷考虑到当地地形、气候、环境等因素给工程带来的困难及做出的解决办法，如微丘地区填方过大可采取高架桥的方式过渡；二、主题部分1、国内道路发展及现状中华人民共和国成立以后。
二级公路设计说明书
广州大学毕业论文（设计）课题名称 XX至XX二级公路设计学院土木工程学院系别道路与桥梁系专业班级学生姓名学号指导教师完成日期 2011年6月9日教务处制摘要：本设计是XX至XX的一段丘陵区二级公路方案设计,公路全长1836.286米。
设计要求在给定的1：2000的带状地形图上，根据给定的原始数据资料，综合考虑平纵横配合与地形特点进行纸上定线，方案比选后对所选方案进行平、纵、横设计，路面设计，其中包括：平面设计、纵断面设计、横断面设计、路基路面排水工程设计（路基设计、路基排水设计、路面工程设计(沥青路面水泥混凝土路面的结构组合设计) ，同时也给出了相关的表格与图纸。
关键词：道路等级，选线，平面设计，纵断面，横断面，路基，路面，设计ABSTRACT：This design is From JIA NAN to FENG JIANG of hills area Class II highway design.The highway is whole long 1836.286 meters. Design requirements in a given band of 1:2000 topographic map, according to the original data set, considered-vertical and horizontal coordination and terrain characteristics of paper alignment, the programme after the election than the selected programme-ping, vertical, Wang design, road design, including: graphic design, profile design, cross-sectional design, embankment road drainage project design (a roadbed design, embankment and drainage design, retaining walls design), Pavement Engineering (for asphalt pavement cement concrete pavement The combination of structural design), but also given the relevant forms and drawings.Keywords：road-grade，alignment，flat surface design，longitudinal section，horizontal section，roadbed，pavement，design目录1.前言 (1)1.1设计条件 (1)1.2设计要求 (1)1.3设计过程 (1)1.4公路修建的意义 (2)1.5主要参考文献 (2)2.道路技术等级的确定 (3)2.1设计资料 (3)2.1.1交通量（辆/日）资料 (3)2.1.2汽车折算系数 (3)2.2交通量计算 (3)2.2.1设计初年年平均日交通量计算 (3)2.2.2远景规划交通量计算 (3)2.3道路等级的确定 (4)3.路线技术指标的论证 (5)3.1直线 (5)3.1.1直线的最小长度 (5)3.1.2直线的最大长度 (5)3.2圆曲线半径及圆曲线长度 (5)3.2.1公式与影响因素 (6)3.2.2最小半径计算 (7)3.2.3圆曲线的最大半径 (8)3.3缓和曲线 (8)3.3.1缓和曲线的最小长度 (8)3.4行车视距 (9)3.4.1停车视距 (9)3.4.2超车视距 (9)3.4.3会车视距 (10)3.5平面视距的保证 (10)3.6纵断面技术论证 (10)3.6.1最大纵坡 (10)3.6.2最小纵坡 (10)3.6.3最小坡长 (10)3.6.4最大坡长 (11)3.6.5缓和坡段 (11)3.6.6竖曲线的最小半径 (11)3.7.1路基宽度 (12)3.7.2道路路拱 (12)3.7.3道路边沟 (12)3.7.4道路边坡坡度 (13)3.8路基技术论证 (13)3.8.1路基设计的基本要求 (13)3.8.2路基宽度 (14)3.8.3路基高度 (14)3.8.4路基压实 (15)3.8.5边坡坡度 (15)3.9路面技术论证 (16)3.9.1路面设计的基本要求 (16)3.9.2路面等级 (16)3.9.3路拱坡度 (16)3.9.4路面排水 (17)3.9.5桥涵 (17)3.10技术指标汇总 (17)4.初步选线与定线设计 (19)4.1路线初步选线 (19)4.1.1选线的主要依据来源 (19)4.1.2选定路线 (19)4.2路线初步定线 (19)4.2.1纸上定线 (19)4.3平曲线初步设计 (21)4.3.1缓和曲线设计 (21)4.3.2路线的转点和转角的确定 (21)4.4纵断面的初步设计 (22)4.4.1平纵线形组合的基本要求 (22)4.4.2纵断面设计的步骤 (23)4.4.3纵断面的竖曲线设计 (23)4.4.4方案比选 (24)4.4.5平面曲线要素的确定 (25)4.4.6缓和曲线的设计 (25)4.4.7初步设计的平曲线加桩 (25)5.纵断面的详细设计 (26)5.1平纵线形组合设计 (26)5.1.1平纵线形组合的设计原则 (26)5.2纵断面详细设计 (27)5.2.1纵断面线形设计的一般要求 (27)5.2.2纵断面设计的步骤 (28)5.2.3纵断面的竖曲线设计 (28)6.1横断面的组成 (30)6.2路拱的确定 (30)6.2.1弯道的超高 (31)6.2.2弯道的加宽 (31)6.2.3陡坡路堤的稳定性检验 (30)6.2.4土石方量计算和调动 (32)6.3路基边坡设计 (32)6.3.1路堤边坡 (32)6.3.2路堑边坡 (32)6.4沟渠设计 (33)6.4.1边沟设计 (33)6.4.2边沟的断面形式 (33)6.4.3边沟断面尺寸 (33)6.4.4沟渠加固 (33)7.水泥混凝土路面设计 (34)7.1交通资料分析 (34)7.2标准轴载及轴载当量换算 (35)7.3标准轴载累计当量作用次数N E 及混泥土路面交通等级的划分 (36)7.3.1其他相关参数的确定 (37)7.4路面结构的初步拟定 (38)7.4.1路面结构层厚度的计算 (38)7.4.2荷载应力分析 (41)7.4.3温度应力分析 (42)7.4.4综合疲劳应力分析 (43)7.4.5水泥混凝土纵缝设计 (44)7.4.6水泥混凝土路面横缝设计 (45)8.沥青路面设计 (46)8.1路面设计计算 (46)8.1.1路面设计年限 (48)8.1.2标准轴载及轴载当量换算 (49)8.2选用原材料 (49)8.3预估路基回弹模量 (51)8.4路面结构的初步拟定 (52)8.4.1路面结构初步拟定 (52)8.4.2路面设计弯沉值计算 (52)8.4.3容许层底拉应力计算 (53)8.4.4半刚性基层沥青路面 (53)8.4.5柔性基层沥青路面 (55)8.4.6最少防冻层验算 (56)8.7.2确定最佳沥青路面结构方案 (57)致谢 (59)参考文献 (60)附录 (61)1.前言1.1设计条件设计为XX至XX的一段丘陵区二级公路常规设计，本公路位于广东省境内，是本省的二级集散公路之一，其设计车速为60km/h,车辆增长率γ为3.7% 。
二级公路设计优秀毕业设计中英文摘要
青岛理工大学毕业设计(论文)摘要本设计根据给定的资料;通过对原始数据的分析;根据该路段的地形、地质、地物、水文等自然条件;根据《公路工程技术标准》、《公路路线设计规范》等交通部颁发的相关技术指标，在老师的指导和同学的帮助下完成的。
设计内业详细资料有:路线设计，包括纸上定线、绘制路线平面图、路线纵断面设计;路基设计，完成五公里横断面和路基土石方的计算及路基排水设计;路面设计，沥青混凝土路面设计;小桥涵设计;设计概预算编制，完成全线设计路段的初步设计概算;施工组织设计;应用计算机绘制工程图，按老师的指导和要求完成。
整个设计计算了平、纵、横要素，设计了路基、路面、小桥涵等内容，通过这次设计了解了公路设计流程。
由此圆满完成了菏泽至定陶二级公路的设计。
本设计为微丘区二级公路，设计车速为 80,,,,。
设计全长5250m，双向两车道，采用二级公路整体式断面标准，设计年限为12年。
该工程计划于2012年4月1日起施工到2012年7月26日完成竣工验收，历时117天。
关键词: 二级公路线形设计路面路基沥青施工组织设计工程造价第69 页青岛理工大学毕业设计(论文)AbstractThis design according to the given information,through the analysis on the original data,according to the sections of the terrain, geology, terrain, hydrology and other natural conditions;According to" technical standard of Highway Engineering"," code for design of highway route", issued by the Ministry of transportation related technical indicators, the guidance of the teacher and students with the help .Design interiordetails : route design, including paper location, drawing the route plan, route vertical section design;The roadbed design, to complete the five km cross sectional and Subgrade Earthwork Calculation and drainage design; design of pavement, asphalt concrete pavement design;Smallbridge culvert design; design budget, complete all sections of theinitial design budgetary estimate of design; construction organization design; application of computer drawing, according to the teacher's guidance and requirements.The design and calculation of the horizontal, longitudinal,transverse elements, design of roadbed, road, bridge and culvert, etc., through this design about highway design process. The successful completion of the Heze to Dingtao two highway design.The design for the hilly area two highway, the design speed of80km / h. Design of full-length5250m, two-way two driveway, using two stage highway integral standard section, design life of 12 years.This project plans in April 1, 2012August 26, 2012 to complete the construction completion and acceptance, which lasted 117 days.Key words: Two stage highway alignment design road surface roadbed Asphalt construction organization planning project cost第70 页。
公路建设外文翻译文献
公路建设外文翻译文献(文档含中英文对照即英文原文和中文翻译)PavementHighway pavements are divided into two main categories: rigitand flexible.The wearing surfaceof a rigid pavement is usually constructed of Portland cement concrete such that it acts like a beam over any irregularities in the underlying supporting material.The wearing surface of flexible pavements, on the other hand, is usually constructed of bituminous material such that they remain in contact with the underlying material even when minor irregularities occur.Flexible pavements usually consist of a bituminous surface underlaid with a layer of granular material and a layer of a suitable mixture of coarse and fine materials.Coarse aggregatesFine aggregatesTraffic loads are transferred by the wearing surface to the underlying supporting materials through the interlocking of aggregates, the frictionaleffect of the granular materials, and the cohesion of the fine materials.Flexible pavements are further divided into three subgroups: high type, intermediate type, and low type. High-type pavements have wearing surfaces that adequately support the expected traffic load without visible distress due to fatigue and are not susceptible to weather conditions.Intermediate-type pavements have wearing surfaces that range from surface treated to those with qualities just below that of high-type pavements. Low-type pavements are used mainly for low-cost roads and have wearing surfaces that range from untreated to loose natural materials to surface-treated earth.✹The components of a flexible pavement include the subgradeor prepared roadbed, the subbase, basecourse, and the surface course (Fig.11.1).✹Upper surface courseMiddle surface courseLower surface courseThe performance of the pavement depends on the satisfactory performance of each component, which requires proper evaluation of the properties of each component separately.✹The subgrade is usually the natural material located along the horizontal alignment of the pavement and serves as the foundation of the pavement structure.✹The subgrademay also consist of a layer of selected borrow materials, well compacted to prescribedspecifications.✹Compacting plantCompaction deviceCompactnessIt may be necessary to treat the subgrade material to achieve certain strength properties required for the type of pavement being constructed.Located immediately above the subgrade, the subbase component consists of a superior quality to that which generally is used for subgrade construction. The requirements for subbase materials are usually given in terms of the gradation, plastic characteristics, and strength. When the quality of the subgrade material meets the requirements of the subbase material, the subbase component may be omitted.In cases where suitable subbase material is not readily available ,the available material can be treated with other materials to achieve the necessary properties. This process of treating soils to improve their engineering properties is know as stabilization.✹The base course lies immediately above the subbase. It is placed immediately above the subgrade if a subbase course is not used.✹This course usually consists of granular materials such as crushed stone, crushed or uncrushed.The specifications for base course materials usually include stricter requirements than those for subbase materials, particularly with respect to their plasticity, gradation, and strength.Materials that do not have the required properties can be used as base materials if they are properly stabilized with Portland cement, asphalt, or lime .In some cases, high-quality base course materials may also be treated with asphalt or Portland cement to improve the stiffness characteristics of heavy-duty pavementsThe surface course is the upper course of the road pavement and is constructed immediately above the base course. The surface course in flexible pavement usually consists of a mixture of mineral aggregates and asphaltic materials.It should be capable of withstanding high tire pressures, resisting the abrasive forces due to traffic, providing a skid-resistant driving surface, and preventing the penetration of surface water into the underlying layers.✹The thickness of the wearing surface can vary from 3 in. to more than 6 in.（inch，英寸，2.54cm）, depending on the expected traffic on the pavement.It was shown that the quality of the surface course of a flexible pavement depends on the mix design of the asphalt concrete used.✹Rigid highway pavements usually are constructed to carry heavy traffic loads, although they have been used for residential and local roads. Properly designed and constructed rigid pavements have long service lives and usually are less expensive to maintain than the flexible pavements.✹The Portland cement concrete commonly used for rigid pavements consists of Portland cement, coarse aggregate, fine aggregate, and water. Steel reinforcing rods may or may not be used, depending on the type of pavement being constructed.Rigid highway pavements be divided into three general type: plain concrete pavements, simply reinforced concrete pavements, and continuously reinforced concrete pavement. The definition of each pavement type is related to the amount of reinforcement used.Plain concrete pavement has no temperature steel or dowels for load transfer.However, steel tie bars are often used to provide a hingeeffect at longitudinal joints and to prevent the opening of these joints. Plain concrete pavements are used mainly on low-volume highways or when cement-stabilized soils are used as subbase.Joints are placed at relatively shorter distances (10 to 20 ft) than with the other types of concrete pavements to reduce the amount of cracking.In some case, the transverse joints of plain concrete pavements are skewed about 4 to 5 ft in plan, such that only one wheel of a vehicle passes through the joint at a time. This helps to provide a smoother ride.Simply reinforced concrete pavements have dowels for the transfer of traffic loads across joints, with these joints spaced at larger distances, ranging from 30 to 100 ft. Temperature steel is used throughout the slab, with the amount dependent on the length of the slab. Tie bars are also commonly used in longitudinal joints.Continuously reinforced concrete pavements have no transverse joints, except construction joints or expansion joints when they are necessary at specific positions, such as at bridges.These pavements have a relatively high percentage of steel, with the minimum usually at 0.6 percent of the cross section of the slab. They also contain tie bars across the longitudinal joints.h/2h/25~10cm填缝料 横向施工缝构造填缝料平缝加拉杆型Bituminous Surface CoursesThe bituminous surface course has to provide resistance to the effects of repeated loading by tyres and to the effects of the environment.✹In addition, it must offer adequate skid resistance in wet weather as well as comfortable vehicle ride. It must also be resistant to rutting and to cracking.✹It is also desirable that surface course is impermeable, except in the case of porous asphalt.Hot rolled asphalt (HRA) is a gapgraded material with less coarse aggregate. In fact it is essentially a bitumen/fine aggregate/filler mortar into which some coarse aggregate is placed.The mechanical propertiesare dominated by those of the mortar. This material has been extensively used as the wearing course on major road in the UK, though its use has recently declined as new materials have been introduced.✹It provides a durablelayer with good resistance to cracking and one which is relatively easy to compact. The coarse aggregate content is low (typically 30%) which results in the compacted mixture having a smooth surface. Accordingly, the skid resistance is inadequate and precoated chippings are rolled into the surface at the time of laying to correct this deficiency.In Scotland, HRA wearing course remains the preferred wearing course on trunk roads including motorway but，since 1999 thin surfacings have been the preferred option in England and Wales. Since 1999 in Northern Ireland, HRA wearing course and thin surfacings are the preferred permitted options.Porous asphalt (PA) is a uniformly graded material which is designed to provide large air voids so that water can drain to the verges within the layer thickness. If the wearing course is to be effective, the basecourse below must be waterproof and the PA must have the ability to retain its open textured properties with time.Thick binder films are required to resist water damage and ageing of the binder. In use, this material minimizes vehicle spray, provides a quiet ride and lower rolling resistance to traffic than dense mixtures.✹It is often specified for environmental reasons but stone mastic asphalt (SMA) and special thin surfacings are generally favoured in current UK practice.There have been high profile instances where a PA wearing course has failed early in its life. The Highways Agency does not recommend the use of a PA at traffic levels above 6000 commercial vehicles per day.✹Asphaltic concrete and dense bitumen macadam (DBM) are continuously graded mixtures similar in principle to the DBMs used in roadbases and basecourses but with smaller maximum particle sizes. Asphaltic concrete tends to have a slightlydenser grading and is used for road surfaces throughout the world with the excepting of the UK.✹It is more difficult to meet UK skid resistance Standards with DBMs than HRA, SMA or PA. This problem can be resolves by providing a separate surface treatment but doing so generally makes DBM economically unattractive.✹Stone mastic asphalt (SMA) material was pioneeredin Germany and Scandinavia and is now widely used in the UK. SMA has a coarse, aggregrate skeleton, like PA, but the voids are filled with a fine aggregate/filler /bitumen mortar.✹In mixtures using penetration grade bitumen , fibres are added to hold the bitumen within the mixture (to prevent “binder drainage”).Bitumen✹oil bitumen( earth oil)✹natural bitumen✹TarWhere a polymer modified bitumen is used, there is generally no need for fibres. SMA is a gap-graded material with good resistance to rutting and high durability. modified bitumen✹SBS✹SBR✹PE\EV A✹It differs from HRA in that the mortar is designed to just fill the voids in the coarse aggregate whereas, in HRA, coarse aggregate is introduced into the mortar and does not provide a continous stone matrix. The higher stone content HRAs ,however, are rather similar to SMA but are not wide used as wearing courses in the UK, being preferred for roadbase and basecourse construction.A variety of thin and what were called ultra thin surfacings (nowadays, the tendency is to use the term …thin surfacings‟ for both thin and ultra thin surfac ings ) have been introduced in recent years, principally as a result of development work concentrated in France.These materials vary in their detailed constituents but usually have an aggregate grading similar to SMA and often incorporate a polymer modified bitumen.They may be used over a high stiffness roadbase and basecourse or used for resurfacing of existing pavements. For heavy duty pavements (i .e those designed to have a useful life of forty years), the maintenance philosophy is one of minimum lane occupancy, which only allows time for replacement of the wearing course to these …long life‟ pavement structures. The new generation of thin surfacings allows this to be conveniently achieved.The various generic mixture types described above can be compared with respect to their mechanical properties and durability characteristics by reference to Fig.12.1. This shows, in principle, how low stone content HRA, asphaltic concrete, SMA and PA mixtures mobilize resistance to loading by traffic.Asphaltic concrete (Fig.12.1a)) presents something of a compromise when well designed, since the dense aggregate grading can offer good resistance to the shear stresses which cause rutting, while an adequate binder content will provide reasonable resistance to the tensile stresses which cause cracking.In general, the role of the aggregate dominates. DBMs tend to have less dense gradings and properties which, therefore, tend towards good rutting resistance andaway from good crack resistance.HRA (Fig.12.1b)) offers particularly good resistance to cracking through the binder rich mortar between the coarse aggregate particles. This also provides good durability but the lack of coarse aggregate content inhibits resistance to rutting.SMA and PA are shown in the same diagram ( Fig.c)) to emphasis the dominant role the coarse aggregate. In both case, well coated stone is used. In PA, the void space remains available for drainage of water, whilst in SMA, the space is occupied by a fine aggregate/ filler/ bitumen/ fibre mortar.Both materials offer good rutting resistance through the coarse aggregate content. The tensile strength of PA is low whilst that of SMA is probably adequate but little mechanical testing data have been reported to date.Drainage for Road and Airports✹Provision of adequate drainage is important factor in the location and geometric design of road and airports. Drainage facilities on any highway, street and airport should adequately provide for the flow of water away from the surface of the pavement to properly designed channels.Inadequate drainage will eventually result in serious damage to the structure.✹In addition, traffic may be slowed by accumulated water on the pavement, and accidents may occur as a result of hydroplaning and loss of visibility from splash and spray. The importance of adequate drainage is recognized in the amount of highway construction dollars allocated to drainage facilities. About25 percent of highway construction dollars are spent for erosion control anddrainage structures, such as culverts, bridges, channels, and ditches.✹Highway Drainage Structures✹One of the main concerns of the highway engineer is to provide an adequate size structure, such that the waterway opening is sufficiently large to discharge the expected flow of water.Inadequately sized structures can result in water impounding, which may lead to failure of the adjacent sections of the highway due to embankments being submerged in water for long periods.✹The two general categories of drainage structures are major and minor. Major structures are those with clear spans greater than 20 feet, whereas minor structures are those with clear spans of 20 feet or less .✹Major structures are usually large bridges, although multiple-span culverts may also be included in this class. Minor structures include small bridges and culverts.Emphasis is placed on selecting the span and vertical clearancerequirements for major structures. The bridge deck should be located above the high water mark .The clearance above the high water mark depends on whether the waterway is navigable ✹If the waterway is navigable, the clearance above the high water mark should allow the largest ship using the channel to pass underneath the bridge without colliding with the bridge deck. The clearance height, type, and spacing of piers also depend on the probability of ice jams and the extentto which floating logs and debris appear on the waterway during high water.✹An examination of the banks on either side of the waterway will indicate the location of the high water mark, since this is usually associated with signs of erosion and debris deposits. Local residents, who have lived near and observed the waterway during flood stages over a number of years, can also give reliable information on the location of the high water mark. Stream gauges that have been installed in the waterway for many years can also provide data that can be used to locate the high water mark.Minor structures, consisting of short-span bridges and culverts, are the predominant type of drainage structures on highways. Although openings for these structures are not designed to be adequate for the worst flood conditions, they shouldbe large enough to accommodate the flow conditions that might occur during the normal life expectancy of the structure.✹Provision should also be made for preventing clogging of the structure due to floating debris and large boulders rolling from the banks of steep channels.✹Culverts are made of different materials and in different shapes. Materials used to construct culverts include concrete（reinforced and unreinforced）, corrugated steel, and corrugatedaluminum. Other materials may also be used to line the interiorof the culvert to prevent corrosion and abrasionor to reduce hydraulic resistance. For example, asphaltic concrete may be used to line corrugated metal culverts. The different shapes normally used in culvert construction include circular, rectangular (box), elliptical, pipe arch, metal box, and arch.✹The drainage problem is increased in these areas primarily for two reasons: the impervious nature of the area creates a very high runoff; and there is little room for natural water courses. It is often necessary to collect the entire storm water into a system of pipes and transmit it over considerable distances before it can be loosed again as surface runoff. This collection and transmission further increase the problem, since all of the water must be collected with virtually no pending, thus eliminating any natural storage; and through increased velocity the peak runoffs are reached more quickly.Also, the shorter times of peaks cause the system to be more sensitive to short-duration,high intensive rainfall.Storm sewers,like culverts and bridges,are designed for storms of various intensity-return-period relationships, depending upon the economy and amount of ponding that can be tolerated.✹Airport Drainage✹The problem of providing proper drainage facilities for airports is similar in many ways to that of highways and streets. However, because of the large and relatively flat surface involved, the varying soil conditions, the absence of natural water courses and possible side ditches, and the greater concentration of discharge at the terminus of the construction area, some phases of the problem are more complex. For the average airport the over-all area to be drained is relatively large and an extensive drainage system is required. The magnitude of such a system makes it even more imperative that sound engineering principles based on all of the best available data be used to ensure the most economical design.Overdesigning of facilities results in excessive money investment with no return, and underdesigning can result in conditions hazardous to the air traffic using the airport. In order to ensure surfaces that are smooth, firm, stable, and reasonably free from flooding, it is necessary to provide a system which will do several things.It must collect and remove the surface water from the airport surfaces; intercept and remove surface water flowing toward the airport from adjacent areas; collect and remove any excessive subsurface water beneath the surface of the airport facilities and in many cases lower the ground-water table; and provide protection against erosion of the sloping areas.路面公路的路面被分为两类：刚性的和柔性的。
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外文资料及翻译Effects of Design Features on Rigid Pavement PerformanceThe performance of rigid pavements is affected by a variety of design features, including slab thickness, base type, joint spacing, reinforcement, joint orientation, load trans fer, dowel bar coatings, longitudinal joint design, joint sealant, tied concrete shoulders ,and subdrainage . A study was made by ERES Consultants, Inc. under FHWA contract on the effects of these features on rigid pavement performance . Ninety-five pavemen tsections located in four major climatic regions were thoroughly evaluated . The following conclusions, which provide some revealing insights into pavement performance, are abstracted from the report (Smith et al., 1990a).Slab Thickness The effect of slab thickness on pavement performance was significant.It was found that increasing slab thickness reduced transverse and longitudinal cracking in all cases. This effect was much more pronounced for thinner slabs than fo rthicker slabs . It was not possible to compare the performance of the thinner slabs and the thicker slabs directly, because the thick slabs were all constructed directly on th esubgrade and the thinner slabs were all constructed on a base course .Increasing the thickness of slab did not appear to reduce joint spalling or join tfaulting . Thick slabs placed directly on the subgrade, especially in wet climates an dexposed to heavy traffic, faulted as much as thin slabs constructed on a base course .Base Type Base types, including base/slab interface friction, base stiffness, base erodibility, and base permeability, seemed to have a great effect on the performance of jointed concrete pavements . The major performance indicators, which were affected by variations in base type, were transverse and longitudinal cracking, joint spalling, and faulting .The worst performing base type, consisted of the cement-treated or soil cement bases, which tended to exhibit excessive pumping, faulting, and cracking. This is most likely due to the impervious nature of the base, which traps moisture and yet can brea- k down and contribute to the movement of fines beneath the slab .The use of lean concrete bases generally produced poor performance . Large curl -ing and warping stresses have been associated with slabs constructed over lean concrete bases. These stresses result in considerable transverse and longitudinal cracking of the slab . The poor performance of these bases can also be attributed to a bathtub design, in which moisture is trapped within the pavement cross section .Dense-graded asphalt-treated base courses ranged in performance from very poor to good. The fact that these types of bases were often constructed as a bathtub design contributed to their poor performance . This improper design often resulted in severe cracking, faulting, and pumping.The construction of thicker slabs directly on the subgrade with no base resulted In a pavement that performed marginally. These pavements were especially susceptible to faulting, even under low traffic levels.Pavements constructed over aggregate bases had varied performance, but were generally in the fair to very good category. In general, the more open-graded the aggregate,the better the performance . An advantage of aggregate bases is that they contribute the least to the high curling and warping stresses in the slab . Even though aggregate bases are not open-graded, they are more permeable and have a lower friction factor than stabilized bases .The best bases in terms of pavement performance were the permeable bases . Typical base courses have permeabilities ranging from 0 to less than 1 ft/day (0 .3 m/day) ; good permeable bases have permeabilities up to 1000 ft/day (305 m/day) . Specific areas of concern were the high corner deflections and the low load transfer exhibited by the permeable bases . These can affect their long-term performance, so the use of dowel bars might be required . An unexpected benefit of using permeable bases was the reduction in "D" cracking on pavements susceptible to this type of distress .Slab Length For JPCP, the length of slabs investigated ranged from 7 .75 to 30 ft(2.4to9.1m). It was found that reducing the slab length decreased both the magnitude of the joint faulting and the amount of transverse cracking. On pavements with random joint spacings, slabs with joint spacings greater than 18 ft (5.5 m) experienced more transverse cracking than did the shorter slabs .For JRCP, the length of slabs investigated ranged from 21 to 78 ft (6 .4 to 23 .9 m) .Generally, shorter joint spacings performed better, as measured by the deteriorated transverse cracks, joint faulting, and joint spalling . However, several JRCP with long joint spacings performed quite well . In particular, the long jointed pavements in New Jersey, which were constructed with expansion joints, displayed excellent performance .An examination of the stiffness of foundation was made through the use of the radius of relative stiffness, f . Generally speaking, when the ratio L/E, where L is the length of slab, was greater than 5, transverse cracking occurred more frequently . Thisfactor was further examined for different base types . It was found that stiffer base courses required shorter joint spacings to reduce or eliminate transverse cracking .Reinforcement The amount of steel reinforcement appeared to have an effect in controlling the amount of deteriorated transverse cracking . Pavement sections with less than 0.1% reinforcing steel often displayed significant deteriorated transverse cracking.A minimum of 0 .1% reinforcing steel is therefore recommended, with larger amounts required for more severe climate and longer slabs.Joint Orientation Conventional wisdom has it that skewed joints prevent the application of two wheel loads to the joint at the same time and thus can reduce load-associated distresses . The results from the limited sample size in this study were ambiguous, but all of the nondoweled sections with skewed joints had a lower PSR than similar designs with perpendicular joints . The available data provide no definite conclusions on the effectiveness of skewing transverse joints for nondoweled slabs . Skewed joints are not believed to provide any benefit to doweled slabs.Load Transfer Dowel bars were found to be effective in reducing the amount of joint faulting when compared with nondoweled sections of comparable designs. The diameter of dowels had an effect on performance, because larger diameter bars provided better load transfer and control of faulting under heavy traffic than did smaller dowels.It appeared that a minimum dowel diameter of 1 .25 in . (32 mm) was necessary to provide good performance .Nondoweled JPCP slabs generally developed significant faulting, regardless of pavement design or climate . This effect was somewhat mitigated by the use of permeable bases. However, the sections in this group had a much lower number of accumulated ESAL, so no definite conclusions can be drawn yet .Dowel Bar Coatings Corrosion-resistant coatings are needed to protect dowels from the adverse effects of moisture and deicing chemicals .While most of the sections in this study did not contain corrosion-resistant dowel bars, those that did generally exhibited enhanced performance. Very little deteriorated transverse cracking was identified on these sections. In fact, one section in New Jersey with stainless steel-clad dowel bars was performing satisfactorily after 36 years of service .Longitudinal Joint Design The longitudinal joint design was found to be a critical design element.Both inadequate forming techniques and insufficient depths of joint can contribute to the development of longitudinal cracking . There was evidence of the ad vantage of sawing the joints over the use of inserts . The depth of longitudinal joints is generally recommended to be one-third of the actual, notdesigned, slab thickness, but might have to be greater when stabilized bases are used .Joint Sealant Joint sealing appeared to have a beneficial effect on performance . This was particularly true in harsh climates with excessive amounts of moisture . Preformed compression sealants were shown to perform well for more than 15 years under heavy traffic.Except where "D" cracking occurred, pavement sections containing preformed sealants generally exhibited little joint spalling and were in good overall conditions.Rubberized asphalt joint sealants showed good performance for 5 to 7 years.Tied Concrete Shoulders It is generally believed that tied concrete shoulders can reduce edge stresses and corner deflections by providing more lateral supports to the mainline pavement, thus improving pavement performance . Surprisingly, this study showed that, although tied concrete shoulders performed better than asphalt shoulders,many of the tied shoulders were not designed properly and actually contributed to poor performance of the mainline pavement . The tiebars were spaced too far apart ,sometimes at a spacing of 40 in.(1016 mm), and were not strategically located near slab corners to provide adequate support . In some cases, tied concrete shoulders were constructed over a stabilized dense-graded base in a bathtub design, resulting in the poor performance of mainline pavement.Subdrainage The provision of positive subdrainage, either in the form of longitudinal edge drains or the combination of a drainage layer and edge drains, generally reduced the amount of faulting and spalling related to "D" cracking . With few exceptions, the load-associated distresses, especially faulting and transverse cracking, decreased as the drainage characteristics improved . The overall pavement performance can be improved by using an open-graded base or restricting the percentage of fines . A filter layer must be placed below the permeable base, and regular maintenance of the outlets must be provided .译文结构特点对刚性路面性能的影响刚性路面的性能受种种结构特点的影响，如板厚、基层类型、接缝间距、钢筋用量、接风方向、荷载传递、传力杆涂层、纵缝设计、接缝填封料、有拉杆混凝土道肩和地下排水等。