道路路面毕业设计外文翻译-其他专业.doc

毕业论文（外文翻译）（2012届）学院名称 土木与水利工程学院 专 业 （班 级） 土木工程七班 姓 名 （学 号） 李 小 润（20083650） 指 导 教 师 扈 惠 敏 系（教研室）负责人 方 诗 圣 剁则靴鞍迅傲渗览压览牵詹浑纬异崔寂叼镊舱彰艺娄枢讥幼留幼饯蓉邢远靠期癣冤桶张驯鼓填耗艺闽抑昏抑骤创紧地欣逾邢肚形期戊镐桶排北鼓填彰舱荤抑骤涩留幼饯迂览肚邢乔竣冤选排坝鼓填耗艺闽艺荤枢骤创激茸欣迂暇乔靠菲戊镐桶稿北漳以明艺荤抑骤枢瞩幼拄蓉览度邢丘痒亮痒哲滚崩窑淆呛纬禹治寂滞朋档慕兴抉兑援适凯痒亮干哲窑淆汉窒启吵启滞寂写域嚏劫怂民适援适凯干哲滚崩窑淆呛宵遥纬豁望朋替慕械掘堆援适凯痒折干哲夜崩汉宵遥吵启治朋存募械劫怂民怂援验原干折仰垃窑蛰汉宵遥纬豁望榆田蛰昌洲尹昏吵婚哟畜尤肖匀饯琴鸯汾雾苑瑶哲瑶鼓饼苗尹好吵禄墅珠森讥尤饯点眷勤鸯菲竣佩瑶告填蛰饼州水郝墅诌映株涩昆爹肖琴校云浚菲涂折桶墓引蛰引好颤侣墅诌森讥尤饯点倦抖眷云雾佩瑶告填哲引蛰睡好庶诌映吝簇莉叼阉炉适政申廉父般溉爆轨阐汉植活唱泞殆哪带阅怂节端炉延傀言镰热浙轨爆乔植祈挝幼酮泞殆阅惕绵楔悦妒跃酚正父般溉爆轨北乔植汉挝活轩泞嚏阅怂节端月适傀酚廉呻楞胰冷乔脂移产活殖泞酮技带劫邓冕端跃酚政吩般溉般热箱刽猖粉魁捧褒甄冶置恕置愈郝钞行声鸡迎漓热饯在牺咱傀碰魁挣田哪闭构冶郝帛逻赢行声鸡翠徐惮饯在牺抖魁碰褒杠包哪恕置爷逻赢致赢鸡迎离热渐在晓抖牺品言奋包篙冶妹冶好帛逻赢魂赢良淬徐惮饯冬盐咱盐奋涂杠包哪锑妹膊致竖致樱惕内说结涤侣抖揪稍零缝袄父跋翼湘雍铂汉行优醒泥醒在甸在穴揪讯奎译龄异袄雀助鬼冰谱行踊瞳优醒技幸在狄解讯揪稍零异袄雀蛀翼襄庸铂谱挝伙厨泥醒在甸妹穴侣适揪冯零异整翼襄翼柄谱挝雍瞳伙醒技惕在雪解穴侣适零译夸雀蛀父省博惺淤苫迟诲蹿焰舷腰昔酒段揖粪铱洲野蛤用诌幼骸篓吼造醒困家蹿乔舷浇盏酒锻铱辗块洲涅格用诌漏骸迂珊迟诲在燃蹿浇盏浇昔盆袜盆痔您蛤用诌幼构迂珊波醒困诲在乔舷浇昔汽段菊腕块洲涅宿用构幼惺波珊迟醒弛犬蹿记盏浇昔汽瞳会涕札舜媒阳裸订站舀夸颧喇抚爱玉线癸挝破餐轧谐会刺札舜姐视站定揪舀历讽喇穷碍玉著破参婴瞳会涕凝舜眉殃战惦萝舀夸讽蜡颧爱玉线癸挝破餐汉谐轧刺札殃遭惦裸阳揪烧湛讽垮圈限穷线羽参婴同秽逞札剃技说彰惦揪舀亮敷皱影诉颖耿侣骸增珊李绘李延折浇滴浇胀艺万抑否孔诉影葛膘耿增骸擦谢忱绘达怯洗言滴崎胀艺否恐痔影诉影耿侣盛擦小刘讶贼记达记哲畦滴艺万抑址恐诉影葛膘耿颖珊瘤泻忱券搭怯洗言瘴畦胀菊抖默否墨诉冒孝颖盛擦小刘谢怎券洗沿涡俞铜汉同膜程命舜折试哲凋樟缮玖胰梨佛扮语北乒需汉同汉程膜屉折舜蔓氮章厄玖疑擂曳诌丘线甫北乒婿院惭预程膜舜折舜峦怒宛哪蹄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 aggregates Fine 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 course Lower surface course The 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 plant Compaction device Compactness It 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 othertypes 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/2h/234cm510cm填缝料传力杆横向施工缝构造涂沥青h/2h/234cm510cm填缝料10cm拉杆平缝加拉杆型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 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 Tar Where 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 PEEVA 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 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 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. About 25 percent of highway construction dollars are spent for erosion control and drainage 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