1、西安科技大学高新学院毕业设计(论文)外文翻译学生姓名: 杨雯 院(系): 建筑与土木工程学院 专业班级: 土木工程 0910 班 指导教师: 张玥 完成日期: 2012 年 12 月 16 日 要 求1.外文翻译是毕业设计(论文)的主要内容之一,学生必须独立完成。2.外文翻译文内容应与学生的专业或毕业设计(论文)内容相关,不得少于 15000 印刷字符。3.外文翻译文用 A4 纸打印。文章标题用 3 号宋体,章节标题用 4 号宋体,正文用小 4 号宋体;页边距上下左右均为 2.5cm,左侧装订,装订线 0.5cm。按中文翻译在上,外文原文在下的顺序装订。4.年月日等的填写,用阿拉伯数字书写,要
2、符合关于出版物上数字用法的试行规定 ,如“2009 年 2 月 15 日” 。5.所有签名必须手写,不得打印。沥青面层含骨料的沥青是当今最常见的路面。它们可用于各种道路,从最高等级多层沥青混凝土的高速公路道很少用的薄面防尘公路。 前期处理:在许多类型沥青路面的施工过程中,均采用涂底层或粘底层这道施工工序。 底层:液体沥青材料用以渗透入基层表面,然后在其上铺筑沥青路面。底层把基层表面松散的粒料粘在一起,以保护免遭气象、车辆荷施工设备的破坏,同时便于在其上铺筑沥青路面。粘层:是一种沥青材料,用于新旧表面与覆盖盖表面的混合材料之间的粘结。可在底层上在铺粘层,粘层可用作热沥青膏或液态沥青材料。沥青表面
3、处理:通常是在喷洒沥青之后立即摊铺一层骨料,然后进行碾压。若只喷洒一层沥青,然后摊铺一层骨料,就称为单层表面处理。再喷洒一层沥青,并且再摊铺一层细粒骨料,则路面的厚度,从而可得到两层或三层沥青表面处理。采用沥青表面处理,可用于面层防水以避免基层或路基变软,并且可以防止因交通或螺旋桨冲击波而造成路面得磨损、剥落、粉化和老化。它们尤其适用于老化了得沥青路面,以及坚固基层上承受轻荷载得磨耗层。封闭层:单层表面处理的一种特殊形式,它是许多沥青路面施工的最后一层。封闭层不能用于喷气飞机跑道的沥青混凝土路面上。渗透型碎石路面:渗透型碎石路面与所有其他沥青粒路面的区别在于渗透型碎石路面是在集料铺筑在基层上之
4、后再喷洒沥青材料。将粗糙、有棱角的碎石铺筑在路上,经过压实。然后喷洒沥青材料渗透层,再用细石子覆盖表面,经过碾压、清扫、使颗粒填充于面层的空隙中。渗透型碎石尤其适用于基层。实践证明,混凝土常见的裂缝,大多数是不同深度的表面裂缝,其主要原因是温度梯度造成寒冷地区的温度骤降也容易形成裂缝。因此说混凝土的保温对防止表面早期裂缝尤其重要。从温度应力观点出发,保温应达到下述要求:1)防止混凝土内外温度差及混凝土表面梯度,防止表面裂缝。2)防止混凝土超冷,应该尽量设法使混凝土的施工期最低温度不低于混凝土使用期的稳定温度。3)防止老混凝土过冷,以减少新老混凝土间的约束。混凝土的早期养护,主要目的在于保持适宜
5、的温湿条件,以达到两个方面的效果,一方面使混凝土免受不利温、湿度变形的侵袭,防止有害的冷缩和干缩。一方面使水泥水化作用顺利进行,以期达到设计的强度和抗裂能力。适宜的温湿度条件是相互关联的。混凝上的保温措施常常也有保湿的效果。从理论上分析,新浇混凝土中所含水分完全可以满足水泥水化的要求而有余。但由于蒸发等原因常引起水分损失,从而推迟或防碍水泥的水化,表面混凝土最容易而且直接受到这种不利影响。因此混凝土浇筑后的最初几天是养护的关键时期,在施工中应切实重视起来。水泥混凝土路面的特点是在养护良好的条件下使用年限比其它路面长,但一旦开始破损,将会迅速发展。因此,必须作好预防性、经常性养护。通过经常的巡视
6、观察,及早发现缺陷,查清原因,不失时机地采取适当的措施,以保持路面状况的完好。水泥混凝土路面的经常性养护要做到“四勤” ,即勤扫、勤灌、勤削、勤疏;“四要” ,要配备必要的养护设备,要管好公路绿化,要配合好公路划线,要协助搞好路政管理工作。现场拌制沥青混合料路面(路拌):路拌沥青混合料的施工就使是在路边或跑道上将沥青与集料直接拌合,可用普通的施工设备或移动式搅拌机来拌合。如果混合料需求量不大并且合适的天然集料就在施工现场附近,则采用路拌沥青混合料铺筑公路路面较为经济。它们不适合于铺筑永久性路面,但可用作临时公路的磨耗层或用作较高级公路阶段性施工的第一步。热拌沥青混凝土路面(厂拌):沥青混凝土是
7、粗集料、细集料、矿物料合沥青材料以一定比例在中心拌合厂配制而得的混合料,热拌沥青混凝土是在较高温度下拌合、摊铺并压实的。粗集料是指 10 号筛以上的筛余粒料;细集料是指通过 10 号筛筛孔但在 200号筛上余留的粒料;矿物料是通过 200 号筛的粉料。沥青混凝土的粗集料比例超过 35%45%。片状沥青混凝土:是由砂、填料、沥青膏严格按比例混合加热拌合而形成的一种高质量片状沥青混合料,常用作路面表层。Bituminous SurfaceBituminous materials combined with aggregates are the most common pavement surfac
8、es in use today .They are used on all types of roadway from multiple layers of asphalt concrete on the highest class of highway to thin, dust-control layers on seldom-used roads.Cement concrete road surface is characterized by good conditions in the conservation useful life than other road long, but
9、 once started damaged, will develop rapidly. Therefore, the need to make preventive and regular maintenance. Through regular visits to observe, early detection of errors, identify reasons, lost no time in taking appropriate measures to maintain good road conditions. Cement demands of the regular roa
10、d maintenance to be “four ground,“ that is, ground forces, ground irrigation, ground cut, ground early; “4“ should be equipped with the necessary conservation equipment must control the highways Green, along with good roads, to help improve the management of Highways.Preliminary TreatmentsIn the con
11、struction of many types of bituminous pavements, a prime coat or tack coat is employed as part of the construction procedure.Prime Coat Liquid bituminous material applied to penetrate the surface of a base on which a bituminous pavement is to be placed. The prime coat is applied to bond together loo
12、se particles on the surface to receive the bituminous pavement.Tack Coat A bituminous material applied to provide bond between a new or old surface and the mixture with which it is being covered. It may be used in addition to a prime coat and may applied as a hot asphalt cement or as a liquid bitumi
13、nous material. Bituminous Surface TreatmentA bituminous surface treatment is generally constructed by making an application of bituminous material, immediately followed by the application of covering mineral aggregate. The surface is then rolled. If a single application of bituminous material is mad
14、e, followed by a single application of aggregate, it may be called a single surface treatment. The thickness of this type of surface may be increased by the application of additional bituminous material and additional spreads of successively finer aggregate. The result is a double or triple surface
15、treatment.Bituminous surface treatments are used to waterproof the surface in order to prevent softening of the base and subgrade, and to prevent abrasion, raveling, dusting, and disintegration of the surface by traffic or propeller blast. They are especially adapted for surfacing worn or aged bitum
16、inous pavements, and on strong bases as a wearing surface for light loads. Seal Coat A special type of single surface treatment is a seal coat, which is used as a final layer in the construction of many bituminous pavements. Seal coats should never be used on bituminous concrete airfield pavements w
17、hich will be subjected to jet aircraft trafficIn the construction of the concrete, for turnover rate to raise template , demand concrete form removal as soon as possible that build newly often. Should consider the time of form removal appropriatly when concrete temperature is higher than the tempera
18、ture, so as not to cause the superficial early crack of concrete. Build the early form removal newly, cause the stress of drawing greatly on the surface , present the phenomenon that “ temperature is assaulted “. In initial stage of the concrete was built, because heat of hydration was distributed,
19、the surface caused sizable to draw the stress, surface temperature is also higher than temperature at this moment, remove the template at this moment , surface temperature is lowered suddenly, must cause temperature gradient , thus add and draw the stress on the surface , changed and adds with the h
20、eat of hydration stress, in addition, the concrete bes and contracts , the superficial stress of drawing reaches very great number value, have danger of causing the crack, but if cover on the surface with a light heat insulator in time after removing the template , for instance foam sponge ,etc., fo
21、r prevent concrete surface from produce too big stress of drawing, have prominent results.Add muscle influence to large volume temperature stress of concrete very light , because large volume concrete include muscle to be rate very much low. Just influence general armored concrete . On terms that te
22、mperature is not very high and the stress is less than surrendering terminally, every performance of the steel is steady, and have nothing to do with stress state , time and temperature. Line bloated coefficient of steel and concrete line bloated coefficient difference very light, take place little
23、internal stress very only between the two while changing in temperature. Because the modulus of elasticity of the steel is 75 times of the modulus of elasticity of concrete, when reaching tensile strength and fracturing in interior concrete stress, the stress of the reinforcing bar will not exceed 1
24、0000kg/ cm2. . So, the difficulty of wanting to make use of reinforcing bar to prevent the appearance of the tiny crack very in the concrete. But the crack in the structure generally becomes numerous, the interval is little, the width and depth are smaller behind adding the muscle. And if diameter o
25、f reinforcing bar detailed and when interval dense, to improve concrete result to resist person who split better. Concrete and armored concrete surface of structure often can take place detailed and shallow crack, among them the great majority belong to and do and draw back the crack. Though this ki
26、nd of crack is generally all relatively light, it stills have certain influence on intensity and durability of the structure.Penetration MacadamPenetration macadam pavement differs from all other bituminous in that the bitumen is added to the aggregate after the latter is in place on the base. Coars
27、e, angular, crushed rock is spread and rolled, sprayed with a penetrating coat of bituminous materials , and covered with a smaller stone chip rolled and broomed to fill the voids in the surface . Penetration macadam is well adapted for use as a base course.Mixed-in-place Bituminous Pavements (Road
28、Mix)Mixed-in-place bituminous pavements are constructed by mixing bitumen with aggregate directly on the toad or runway. Mixing may be accomplished by the use of ordinary construction equipment or by traveling mixers. Mixed-in-place pavements provide an economical means of obtaining a satisfactory s
29、urface for roads when the required amount of pavement is small and when suitable natural aggregates are on or near the side. They are not considered suitable for permanent type pavement, but may be used as a wearing course for temporary roads or as the first step in stage construction for higher typ
30、e roads.Hot-Mix Bituminous Concrete Pavements (Plant Mix)Bituminous concrete is an intimate mixture of concrete of coarse aggregate, fine aggregate, mineral filler, and bituminous material, proportioned and mixed at a central mixing plant. Hot-mix bituminous concrete is mixed, spread, and compacted
31、at elevated temperature. Coarse aggregate is material retained on the NO.10 sieve; fine aggregate is that passing the NO.10 sieve and retained on the NO.200; and mineral filler is material finer than NO.200 sieve. Bituminous concrete contains more than 35 to 40 percent coarse aggregate. Sheet AsphaltA hot plant mixture of sand, filler, and asphalt cement carefully proportioned and controlled to produce a sand-type mixture of high quality. It is usually used for surfacing courses.