道路與橋梁專業(yè)英語課后句子

1、道路與橋梁專業(yè)英語課后句子特別感謝：付玉強(qiáng)、劉健、劉明金、劉鑫宇、寧維回、孫清龍第四課課文this force prevents the cracks from developing by eliminating orconsiderably reducing the tensile stresses at the critical sections at servicesload, thereby raising the bending, shear and torsional capacities of thesections.這種力能消除或大大減少使用荷載在跨中及支座等臨界截面處產(chǎn)生的拉

2、應(yīng)力，阻止裂縫出現(xiàn)，從而提高截面的抗彎、抗剪和抗扭能力。although it might appear that the blocks will slip and vertically simulateshear slip failure, in fact they will not because of the longitudinal force p.雖然看起來好像塊體會(huì)滑移并發(fā)生垂直剪切滑動(dòng)破壞，但事實(shí)上由于 縱向力p的作用，這種情況不會(huì)出現(xiàn)。but again, because of the compressive prestress imposed by themetalbands

3、 as a form of circular prestressing, they will remain in place.但乂是由于金屬箍施加的壓應(yīng)力產(chǎn)生了環(huán)形預(yù)應(yīng)力，因而木桶仍保持原樣。linear prestressing had progressed a long way from the early days.線預(yù)應(yīng)力從出現(xiàn)以來，已經(jīng)有了很大的發(fā)展。the success in the development and construction of all these structures has been due in no small measure to the advanc

4、es in the technology of materials, particularly prestressing steel, and the accumulated knowledge inestimating the short and long-term losses in the prestressing forces.所有這些結(jié)構(gòu)物的建造成功，在很大程度上應(yīng)歸功于材料技術(shù)的進(jìn)步，也應(yīng)歸功于預(yù)應(yīng)力損失計(jì)算方法的不斷究善。閱讀材料according to the aashto technology implementation group, hpc, whichis concre

5、te thathas been designed to be more durable, and, if necessary,stronger than conventional concrete, can help highway agencies to buildbridges that are better able to hold p to traffic and environmental demands.根據(jù)美國各州公路與運(yùn)輸工作者協(xié)會(huì)技術(shù)實(shí)施部的論述，高性能混凝土是一種經(jīng)過設(shè)計(jì)后耐久性更好，強(qiáng)度比常規(guī)混凝土更高的混凝土（必要時(shí)），公路部門可以用其修建承受更人車輛荷載和更高環(huán)境要求

6、的橋梁。the section of mix proportions is the process of choosing suitableingredients of concrete and determining their relative quantities with theobject of producing as economically as possible concrete of certain minimumproperties, notably strength, durability and a required consistency.混合料配合比設(shè)計(jì)是在最經(jīng)濟(jì)

7、而滿足強(qiáng)度、耐久性與所需稠度最低性能要求的目標(biāo)下？選擇適宜的混凝土組分并確定其相對(duì)數(shù)量的過程。generally, these methods are based on fundamental functions:water-to-cement ratio the constancy of water demand and theory of optimumaggregates proportioning, all of which determine mixtures with the required properties.這些方法通常都是基于如下基本公式進(jìn)行的：水灰比、恒定用水量與集料最

8、佳配合比理論，他們確?；旌狭夏軡M足相應(yīng)的性能要求。silica fume is also often used in ternary combinations with portlandcement with fly ash or slag.硅粉通常與水泥屮的粉煤灰和礦渣形成三組分結(jié)構(gòu)。the stress-strain behavior is depended on a number of parameters whichinclude material variables such as aggregate type and testing variables such asage at

9、testing, loading rate, strain gradient and others.應(yīng)力應(yīng)變性能取決于各種參數(shù)的取值，包括集料類型等材料變量以及試驗(yàn)齡期、加載速率、應(yīng)變梯度與其他各種試驗(yàn)變量。lesso n 5結(jié)構(gòu)設(shè)計(jì)原理 the successful designer is at all times fully conscious of the variousconsiderations that were成功的設(shè)計(jì)者在任何時(shí)候都能全面的考慮到結(jié)構(gòu)初步設(shè)計(jì)中包含的各種因素，同時(shí)還充分考慮到以后施工中可能遇到的各種問題。特別感謝：付玉強(qiáng)、劉健、劉明金、劉鑫宇、寧維回、孫清龍 t

10、hen comes the analysis (or computation) of the internal gross forces（thrust,shears, .然后開始分析（或計(jì)算）由荷載、溫度、收縮、徐變或其他設(shè)計(jì)因素引起的總內(nèi)力（推力、剪力、彎矩和扭矩）、應(yīng)力強(qiáng)度、應(yīng)變、變形及反力等。 the criteria used to judge whether particular proportions will result inthe desired behavior用來評(píng)價(jià)擬定的（結(jié)構(gòu)）尺寸是否會(huì)獲得預(yù)期性能的準(zhǔn)則反映了知識(shí)的積累（包含理論、現(xiàn)場(chǎng)試驗(yàn)、模型試驗(yàn)和實(shí)踐經(jīng)驗(yàn)）以及直

11、覺和判斷力。 for most common civil engineering structures such as bridges andbuildings, the usual”.對(duì)大多數(shù)諸如橋梁和房屋建筑之類的土木工程結(jié)構(gòu)，過去的常規(guī)做法是根據(jù)以下方法來進(jìn)行設(shè)計(jì)，即把允許應(yīng)力強(qiáng)度和那些由正常使用荷載和其他設(shè)計(jì)因素所產(chǎn)生的應(yīng)力強(qiáng)度作對(duì)比。 depending on the type of structure and conditions involved, thestress intensities computed.根據(jù)結(jié)構(gòu)類型和設(shè)計(jì)條件，在實(shí)際結(jié)構(gòu)的分析模型中由假定的設(shè)計(jì)條件所計(jì)算的

12、應(yīng)力強(qiáng)度與實(shí)際結(jié)構(gòu)在實(shí)際設(shè)計(jì)條件中所產(chǎn)生的應(yīng)力強(qiáng)度可能完全一樣，也可能不一致。 the allowable-stress approach has animportant disadvantage in that it does not provide.允許應(yīng)力法有一個(gè)嚴(yán)重的缺陷，也就是它不能為各類結(jié)構(gòu)及其構(gòu)件給出統(tǒng)一的超載能力。 when proportioning is done on the strength basis,the anticipated service loading is first基于強(qiáng)度的結(jié)構(gòu)比例一旦確定，預(yù)期的使用荷載首先乘以一個(gè)合適的荷載系數(shù)（大于1）。荷載系數(shù)

13、的大小由下列因素確定：荷載的不確定性;結(jié)構(gòu)在其使用壽命期間荷載變化的可能性；對(duì)于荷載組合而言，也與特殊組合的可能性、頻率以及持續(xù)性有關(guān)。 in recent decades, there has been a growing concern among manyprominent engineers that.最近幾十年來，很多著名的工程師已經(jīng)逐漸注意到，“安全系數(shù)”的定義不僅不適當(dāng)，不符合實(shí)際情況，更糟糕的是，基于這種概念上的結(jié)構(gòu)設(shè)計(jì)原理在很多情況下會(huì)導(dǎo)致過分保守，不經(jīng)濟(jì)的設(shè)計(jì)，而在有些情況下又會(huì)出現(xiàn)破壞概率太高的冒險(xiǎn)設(shè)計(jì)。 they feel, therefore, that the va

14、riations of the load effects and thevariations of the structural因此，他們感到，荷載作用和結(jié)構(gòu)抗力的變化應(yīng)該用統(tǒng)計(jì)的方法研究，結(jié)構(gòu)殘留概率或結(jié)構(gòu)正常使用概率也應(yīng)估計(jì)出來。閱讀材料結(jié)構(gòu)分析 such models are based on idealizations of the structural behavior ofthe material and are,".這些模型是基于材料的結(jié)構(gòu)特性理想化建立的，因此，在某種程度上不僅完美，這與建模時(shí)的簡(jiǎn)化假定冇關(guān)。 structural design involves th

15、e arrangement and proportioning ofstructures and their ".結(jié)構(gòu)設(shè)計(jì)包含結(jié)構(gòu)布置和結(jié)構(gòu)及其構(gòu)件的尺寸設(shè)計(jì)。所形成的結(jié)構(gòu)應(yīng)該能夠在整個(gè)使用年限內(nèi)，承受允許范圍內(nèi)的設(shè)計(jì)荷載。 variable loads are also referred to as live （or imposed） loads, andinclude those caused by.".可變荷載亦指活載（或沖擊荷載），同時(shí)還包含除移動(dòng)荷載（如車輛、火車等）之外，由施工作業(yè)、封、地震、學(xué)、爆破以及溫度變化引起的荷載。 a structure that i

16、s initially at rest and remains at rest when actedupon by applied loads is.當(dāng)結(jié)構(gòu)處于靜止?fàn)顟B(tài)，以及在使用荷載作用下仍處于靜止?fàn)顟B(tài)時(shí)，（我們）稱該結(jié)構(gòu)處于平衡狀態(tài)。第八課the basic principle for locating highways is that roadway elements suh ascurvature and grade must blend with each other to produce a system thatprovides for the easy flow of traf

17、fic at the ddesign capacity,while meetingdesign criteria and safety standards定線的基本原則是車行道要素如巧道和坡度必須互相結(jié)合，在滿足設(shè)計(jì)規(guī)范和安全標(biāo)準(zhǔn)的要求的同時(shí)，提供滿足設(shè)計(jì)通行能力并且平穩(wěn)的交通流體系for example,if it is found that a site of historic and archeologicalimportance is located within an area being considered for possible routelocation,it maybe

18、immediately decided that any route that traverses that sitashouldbe excluded from further consideration特別感謝：付玉強(qiáng)、劉健、劉明金、劉鑫宇、寧維回、孫清龍例如，如果發(fā)現(xiàn)一個(gè)重要的歷史古跡和建筑位于路線可能通過的區(qū)域，則應(yīng)立即確定通過那個(gè)區(qū)域的任何路線下一步將不被考慮the availability of computer-based techniques has significantly anhancedthis process since a proposed highway can

19、be displayed on a monitor, enabling the designer to have a drivers eye view of both the horizontal and vertical alignments of the road計(jì)算機(jī)技術(shù)極大地提高了定線過程（的效率），因?yàn)樵O(shè)計(jì)的公路可以顯示在屏幕上，從而使設(shè)計(jì)者有了駕駛者的實(shí)現(xiàn)效果，即可以看到平面線形，又可以看到縱面線性most arterials have 12-ft travel lanes since the xtra cost for constructing12-ft lanes over 1

20、0-ft lanes is usually offset by the lower maintenance cost forshoulders and pavement surface, residing in thereduction of wheelconcentrations at the pavement edges大多數(shù)干線車行道寬12英尺，因?yàn)樾藿?2英尺車行道比10英尺車行道超出費(fèi)用通常被路肩和路面較少的養(yǎng)護(hù)費(fèi)抵消了，可以減輕路面邊緣的輪載集中現(xiàn)象the usable width is the same as the graded width when the side slop

21、e isequal to or flatter than 4;l,as the shoulder break is usually rounded to a widthbetween 41 and 6 ft,thereby increasing the usable width當(dāng)邊坡等于或環(huán)宇4:1 （水平距離：豎直距離）時(shí)，有效路肩寬度與整型路肩寬度相等，因?yàn)槁芳绲霓D(zhuǎn)折處通常被修成圓形，寬度達(dá)到4-6英尺，因此增加了有效寬度the usable median shoulder width for divided arterials with three ormore lanes in eac

22、h diection should be at least 8ft, since drivers in difficulty onthe lane next to the median often find it difficult to maneuover to the outsideshoulder when there is need to stop對(duì)于每一方向有三車道或者更多車道的分離式干線公路，中間帶的有效路肩寬度至少應(yīng)有8英尺，因?yàn)榫o靠屮間帶車道上行駛的駕駛者出現(xiàn)問題需要停車時(shí)，很難行駛到外邊的路肩上。some disadvantages associatedwith raised

23、 medians include possible loss of control of the vehicle by the driverif the median is accidentally struck ,and they cat a shadow from oncomingheadlights, which results in drivers finding it difficult to see the curb凸起式中間帶也有一些缺點(diǎn)，如若司機(jī)不幸撞上中間帶，車輛可能會(huì)失控，對(duì)想車前燈照射下中間帶的陰影會(huì)使駕駛者難以看到路緣石。第十一課l. the wearing surfa

24、ce of a rigid pavement usually is constructed ofportland cement concrete such that it acts like a beam.剛性路面的磨耗層通常用水泥混凝土鋪筑，其受力與梁類似，.high-type pavements have wearing surfaces that adequately support theexpected traffic load without visible distress due to fatigue and are notsusceptible to weather cond

25、itions .高級(jí)路面的磨耗層能奮效的承擔(dān)預(yù)期的車輛荷載，而不會(huì)出現(xiàn)明顯的疲勞破壞，并且不易受氣候的影響。well compacted to prescribed specifications.充分壓實(shí)達(dá)到規(guī)范的要求it should be capable of withstanding high tire pressures,resisting theabrasive forces due to traffic,providing a skid-resistant driving surface,andpreventing the penetration of surface water

26、into the underlying layers.表面層應(yīng)該能夠承受高的輪胎壓力，能夠抵抗車輛的摩阻力，提供良好的抗滑表面，并能阻止表面水滲入下承層。in some cases, the transverse joints of plain concrete pavements areskewed about 4 5ft in plan,such that only one wheel of a vehicle passesthrough the joint at a time.在有些情況下，素混凝土路面的橫向接縫做成傾斜4-5英尺（平面上），這樣，在某一時(shí)刻只有一個(gè)車輪通過接縫。l.lt

27、 is usually assumed that the subgrade layer is infinite in both thehorizontal and vertical directions, whereas the other layers are finite in thevertical direction and infinite in the horizontal direction.通常，假定土層在水平方向及垂直方向均為無限，而其他結(jié)構(gòu)層垂直方向有限，水平方向無限。2. because the accumulated repetitions of traffic loa

28、ds are of significantimportance to the development of cracks and permanent deformation of the pavement.因?yàn)槔塾?jì)重復(fù)荷載對(duì)路面裂縫的發(fā)展以及永久變形會(huì)產(chǎn)生重要的影響。特別感謝：付玉強(qiáng)、劉健、劉明金、劉鑫宇、寧維回、孫清龍3. for example，traffic wheel loads will induce flexural stresses that aredependent on the location of the vehicle wheels relative to edge o

29、f thepavement, whereas expansion and contraction may induce tensile andcompressive stresses, which are dependent on the range of temperaturechanges in the concrete pavement.例如，車輪荷載會(huì)引起彎拉應(yīng)力，其大小取決于車輪與路面邊緣的相對(duì)位置，而溫度脹縮則可能引起拉應(yīng)力與壓應(yīng)力，其大小取決于混凝土路面內(nèi)溫度變化的幅度。4compressive and tensile stresses are therefore induced

30、 at the top andbottom of the slab, respectively , during the day，wherea tensile stressrs areinduced at the top and compressive stresses at the bottom during the night.因此在白天，板頂和版底分別受壓和受拉，而夜晚板頂受拉板底受壓。5. different types of joints are placed in concrete pavements to limit thestresses induced by temperat

31、ure changes and to facilitate proper bonding oftwo adjacent sections of pavement when there is a time lapse between theirconstruction (for example, between the end of one day's work and thebeginning of the next.)混凝土路面內(nèi)設(shè)置了不同類型的接縫來減少溫度變化引起的應(yīng)力，當(dāng)兩個(gè)相鄰板塊施工中斷時(shí)(例如，某f1的最后施工部分和次日的初始施工部分)，需要采取措施形成冇效的連接

32、。第十五課1. the proposed alignment of the highway to be constructed along withthe drainage, utility and geotechnical information provided should bereviewed and a site should be considered essential.應(yīng)審查擬建公路的推薦線位、沿線的排水、公共設(shè)施以及土工技術(shù)資料，實(shí)地考察也是必需的。2. technology is available to feed information of the various co

33、urses to anonboard computer that assists the operator of grading equipment to finishwithin millimeters of the planned elevation.將各層的高程數(shù)據(jù)輸入車載電腦，它將輔助道路平整設(shè)備的操作人員工作，成型誤差在幾毫米范圍內(nèi)，這種技術(shù)己經(jīng)實(shí)現(xiàn)了。3. where good material sources are easily available, embankmentmaterials falling between the classification of a-l-a

34、and a-4 per aashto m145are preferred.該規(guī)范將土按實(shí)驗(yàn)室測(cè)定的粒徑分布、液限與塑性指數(shù)分為七大類，每一大類分為若干小類。4. care should be taken to ensure that these large size materials do notnest to create large voids that could become detrimental to the performanceof the embankment due toexcessive settlement.應(yīng)注意確保大粒徑材料不會(huì)聚稅在一起而形成打的空隙，這些空隙由

35、丁可能產(chǎn)生過大的沉降，對(duì)路堤的性能是有害的。5. an accelerated construction schedule sometimes does not allow forthe use of traditional surcharge of soft subgrade soils and sufficient time forconsolidation settlement to be completed.工程進(jìn)度緊張時(shí)，就沒有足夠的時(shí)間讓軟土地基完成固結(jié)沉降，不能使用傳統(tǒng)的堆載法。6. base course material section is generally carrie

36、d across underneath theshoulders or curb and gutters to not only provide a stable base but also toensure continuity for drainage, away from the surface course of the pavementsection.路妞中的基層材料通常超出妞層延伸至路肩或路緣與邊溝下部，不僅可以提供穩(wěn)定的基礎(chǔ)，而且可以確保排水的連續(xù)性。l. laydowen operations include determination of means to form thesection, given the volume, location and other existing conditions such as bloc