道橋畢業(yè)設(shè)計英文翻譯

1、<p>　　Bridge Engineering</p><p>　　RAMANKUTTY KANNANKUTTY, City of Minneapolis Department of Public Works</p><p>　　DONALD J. FLEMMING, Minnesota Department of Transportation</p><p

2、>　　The scope of the Transportation Research Board’s (TRBs) Committee on General</p><p>　　Structures includes factors affecting the physical behavior, service life, economy,</p><p>　　appearanc

3、e, and safety of bridges and structures for transportation systems, and accounting for these factors and their interactions in design procedures and criteria. During the 20th century the United States has essentially cre

4、ated the safest, most efficient, and most effective highway and intermodal transportation network in the world. The challenge for the new millennium will be to further enhance this transportation network. In this paper t

5、he status of bridge engineering at the end of the 2</p><p>　　BRIDGE STRUCTURE TYPES</p><p>　　Structure types have been evolving throughout history. The evolution will continue into the future, p

6、erhaps at an accelerated rate.The driving forces behind continued advances in bridge engineering are traffic congestion and costs. In the future, just as now, the public will expect few traffic delays, if any. They will

7、want transportation costs to be as low as possible. Computer technology will enhance traffic management so well that the public will become accustomed to flowing traffic and more </p><p>　　grow to such a lev

8、el that interactive design programs will become a necessity. Computer programs that automatically prepare detailed plans incorporating changes at the touch of a button will allow the public to modify or add aesthetic det

9、ails right up to the point that construction begins.</p><p><b>　　Long Span</b></p><p>　　Posttensioning with high-strength materials will allow traditional concrete and steel bridges,

10、especially box shapes, to reach continually longer spans that challenge steel truss bridges ，and even the shorter-span cable-stayed bridges. Cable-stayed bridges and suspension bridges will most likely continue to domina

11、te the long-span bridge category. Long-span bridges will continue to be the most dramatic, capturing the public’s awareness with highly visible and innovative structures. Shown in Figure</p><p>　　Medium Span

12、</p><p>　　Medium spans include spans from 50 to 200 feet and traditionally have been prestressed concrete girders and steel girders. In the future, new materials with high-performance characteristics will be

13、 developed, and the strengths of concrete and steel materials will be enhanced. Stronger materials and innovative design concepts will come together to yield much longer spans. The result will be simpler structures with

14、fewer substructures and a reduction in overall cost. Space frame structures using s</p><p>　　Short Span</p><p>　　Concrete slabs, timber slabs, prestressed concrete shapes, and rolled steel shape

15、s currentlyshare the market for spans up to 50 feet. In the future, these types will be challenged by long-span culverts and preengineered, out-of-the-box, prefabricated component bridges.Shown in Figure 3 is a typical l

16、ong-span culvert (44-foot span) that is starting to challenge more typical short-span structures.</p><p><b>　　DESIGN</b></p><p>　　Designing bridges according to a standard specificat

17、ion became the norm in the 20th</p><p>　　century. This will continue in the next century. However, the process of designing will be much different in the future because of changes in specifications, loads, t

18、esting, and computerization.</p><p>　　Specifications</p><p>　　The specifications used for structural bridge design at the end of the 20th century are split between the American Association of St

19、ate Highway and Transportation Officials (AASHTO) load factor design (LFD) specification and the load and resistance factor design(LRFD) specification, with LRFD recently being designated as the standard for the future.L

20、FD will continue to be used for some time, but its usage will decline as LRFD becomes more widely accepted. Eventually LFD will be discontinued and </p><p>　　because of a lack of accepted methods for analyzi

21、ng and designing foundations. Only afte rmore research and specification enhancement will the situation for substructures change.Widespread usage of LRFD will be somewhat slowed by the lack of computer software.The detai

22、led nature of LRFD code requires that designers develop spreadsheets and other computer worksheets to complete computations efficiently. Introduction of programs such as the AASHTO OPIS computer program will help, but th

23、e full bene</p><p><b>　　Loads</b></p><p>　　At the heart of the load specifician is the design vehicle. The old HS-20 truck, which has been in use since 1944, is being questioned as

24、a vehicle relevant to traffic needs of the 21st century. Early in the century, two specific questions will arise over the continued use of this vehicle. The first question is whether a different vehicle would better matc

25、h the weigh-inmotion (WIM) data coming from the monitoring systems installed in roadways. Though the data are of questionable accuracy, they </p><p>　　Field Testing</p><p>　　To help determine an

26、 appropriate design vehicle, a more comprehensive system of WIM sites will be installed. Because of advances in accuracy and durability of the equipment,dynamic load data will begin to agree with static load data. An acc

27、urate picture will then develop of actual truck axle loads and axle spacings on highway bridges. Emerging technologies such as quartz sensors and fiber-optic enhancements, along with piezo cable,will make more accurate d

28、ata collection possible. Smart bridges w</p><p><b>　　Analysis</b></p><p>　　Computer programs capable of analyzing large amounts of data will be developed. Key design parameters such

29、as distribution factors, multiple presence factors, and uniform loads will be verified. Trends in loadings and the way structures respond to those loadings will be made easier to predict. This may lead to a simplificatio

30、n of design factors and equations, which will allow a drastic improvement in the speed of completing design computations.The design of bridges in the 21st century will be mu</p><p>　　Design Tools</p>

31、<p>　　More and more states will cooperate in the use of standardized details, computer programs,and drafting details, making designs and plans more similar on a regional basis. Such standardization will tend to redu

32、ce construction costs for contractors and suppliers. Speed and accuracy will be increased.After many years of working separately, computer-aided engineering and computeraided drafting will be successfully integrated. Des

33、igns and plans will be iterative and interactive, and plan preparation </p><p>　　design errors. More important, optimization of a design will be a keystroke away. Artificial intelligence will supplement inst

34、itutional memories and expand designers’ options for obtaining real-time expert advice. The need to develop expert systems to check the accuracy and reliability of design software will be a challenge to bridge design pro

35、fessionals.Of course, associated with this challenge is the ever-present debate on professional liability.</p><p>　　Automation</p><p>　　The Internet and e-mail will be standards for communicatio

36、n between designers, fabricators,and contractors. It will become more common for designers and drafters in different states to combine efforts. Correspondence will be handled electronically, eliminating the time necessar

37、y to print and mail correspondence back and forth. Contractors and fabricators will view the final plans electronically.</p><p><b>　　Materials</b></p><p>　　Materials have always play

38、ed a key role in the evolution of bridge structures. Enhancements of the traditional materials of concrete, steel, and timber will continue, but the most revolutionary changes will occur in the areas of fiber-reinforced

39、plastics (FRPs), highstrength and high-performance steel, high-performance concrete (HPC), and the blending of FRP and timber.</p><p><b>　　FRPs</b></p><p>　　Today, FRPs are in their

40、infancy as bridge construction materials. However, further experimentation with various combinations of FRP materials will result in innovative and long-lasting solutions to simple and complex bridge construction issues.

41、 Experimental FRP bridge projects have shown that this material has inherent problems in deflection, material ductility, creep, reactivity with concrete and steel, and performance under long-term exposure to ultraviolet

42、light and other environmental facto</p><p>　　High-Strength and High-Performance Steel</p><p>　　Unlike FRP, high-strength steel materials will be more readily accepted by bridge engineers.Initial

43、 acceptance will be gained because the new steel materials make it possible to reducestructural dead loads. Wider acceptance of high-strength steels will develop because of their enhanced material properties. Gains made

44、in improving material toughness and weldability of high-strength steels will extend to all grades of steel. Design specifications will continue to be updated to deal with material p</p><p><b>　　HPC <

45、;/b></p><p>　　HPC is well on its way to becoming a conventional bridge construction material as a result of Strategic Highway Research Program research and Federal Highway Administration implementation ef

46、forts. The debate as to whether strength or permeability is the primary indicator of long-term durability of HPC will continue among practicing engineers. However, past case studies clearly demonstrate the need for perme

47、ability tests as an indicator of long-term concrete durability. The future is bright for H</p><p><b>　　Timber</b></p><p>　　New processes of reinforcing wood will continue to be devel

48、oped, including the combination of glued-laminated timber and FRP composites. The concept is similar to that of reinforced concrete; wood resists the compression load, while FRP composite resists tensile load. The concep

49、t will be commonly used in future timber structures. Advantages of this technology are in areas where bending strength controls the design (as with lower grades of wood). Reinforcing with FRP greatly increases the tensil

50、e</p><p>　　Other Materials</p><p>　　A significant future challenge for the construction industry will be the incorporation of recycled materials (including plastics), by-products, and waste mate

51、rials into conventional and HPC construction materials. Future environmental regulations and lack of space to store waste products will bring this issue to a head. Significant time and financial resources will be spent i

52、n developing recycled materials into products suitable for use as construction materials.</p><p>　　AESTHETIC CONCERNS</p><p>　　Public Involvement</p><p>　　Public participation in th

53、e design process has increased in recent years because the public wants better aesthetic treatment of bridges, especially bridges considered neighborhood landmarks. Public participation will continue in the future and wi

54、ll likely increase. To facilitate the process, engineers will display plans using three-dimensional visualization technology. The public will be able to view and comment on the plans at hearings or on the Internet.</p

55、><p>　　Interactive Design</p><p>　　Incorporating public comment into the plans will require that last-minute changes be easily accommodated into the design and drafting process. Computer design and

56、 drafting programs that automatically adjust the designs and generate plans will allow for quick modifications. The latest engineering analytical skills will be needed to accommodate this technology. The emphasis on flex

57、ible design will undoubtedly require engineers to increase their aesthetic design skills and overall people skills.</p><p>　　Aesthetic Process</p><p>　　Aesthetic treatment of structures will bec

58、ome so common that only the most remote sites will be unaffected. Nearly all bridges will have a detailed aesthetic treatment, or at least an aesthetic review. Extra planning time and design time will become an accepted

59、part of the cost of a structure. The level of public attention will determine the extent of the aesthetic design process and the resources devoted to aesthetic considerations. Three levels of bridge aesthetic considerati

60、on and processes w</p><p><b>　　橋梁工程</b></p><p><b>　　拉曼克提 卡南克提</b></p><p>　　明尼阿波利斯市公共工程處</p><p><b>　　唐納德J弗萊明</b></p><p>

61、　　明尼蘇達(dá)州交通運輸部</p><p>　　運輸研究委員會委員在一般結(jié)構(gòu)的研究范圍包括影響物理性狀、使用壽命、經(jīng)濟(jì)、外觀的因素，橋梁和交通系統(tǒng)結(jié)構(gòu)安全，在設(shè)計程序及標(biāo)準(zhǔn)中說明這些因素與他們的相互作用。在二十世紀(jì)，美國實質(zhì)上已經(jīng)創(chuàng)造出了世界上最安全、有效而且高效的公路和綜合交通運輸網(wǎng)絡(luò)。新千年的挑戰(zhàn)將會更進(jìn)一步的增強這種交通運輸網(wǎng)絡(luò)，在這片論文中對橋梁工程在二十世紀(jì)末的一般運輸結(jié)構(gòu)中的地位作出了總結(jié)，重點在于橋梁

62、的種類、設(shè)計方面、新材料、審美方面的考慮和主要政策的問題。試圖對預(yù)測橋梁工程在新千年的二三十年內(nèi)的地位作出預(yù)測，這片論文假設(shè)這些預(yù)測會成為現(xiàn)實。</p><p><b>　　橋梁結(jié)構(gòu)種類</b></p><p>　　結(jié)構(gòu)種類在整個歷史過程中一直不停地演變，這種演變會以一種不斷加速的狀態(tài)一直持續(xù)到未來，在橋梁工程持續(xù)不斷進(jìn)步背后的這種驅(qū)動力是交通阻塞和成本。就像現(xiàn)在一樣

63、，在未來公眾同樣不希望發(fā)生交通延誤，如果有任何可能，他們都想要交通成本盡可能低，電腦技術(shù)會提高交通管理效率，這樣公眾能夠習(xí)慣暢通無阻的交通，并且更清楚的知道交通阻塞的位置。從施工中中斷將會更明顯更難以忍受，考慮到這些狀況，結(jié)構(gòu)類型基本上在能夠減少交通延誤的施工速度高的基礎(chǔ)上選擇，低維護(hù)是必須的，能夠容易快速的加寬結(jié)構(gòu)的能力是選擇結(jié)構(gòu)的優(yōu)先問題，在選擇結(jié)構(gòu)類型時安全和審美仍將扮演重要角色，保持子結(jié)構(gòu)獨立于明確區(qū)巷道能夠使跨度更長并且會保證

64、工程社區(qū)最好的跨越，公眾的意見會如此的重要以至于互動的設(shè)計方案會成為必須，自動準(zhǔn)備結(jié)合變化的詳細(xì)方案的一鍵式電腦程序允許公眾在施工開始時改變或添加審美細(xì)節(jié)。</p><p><b>　　新千年的交通運輸</b></p><p><b>　　大跨度</b></p><p>　　高強材料的后張力能夠允許傳統(tǒng)的鋼筋混凝土橋梁，特

65、別是箱形結(jié)構(gòu)，達(dá)到持續(xù)更長的長度，對鋼桁架橋、甚至小跨度斜拉橋形成挑戰(zhàn)。斜拉橋和懸索橋是最有可能繼續(xù)控制大跨度橋梁的種類。大跨度橋梁將會繼續(xù)成為最引人注目的，以高度的觀賞性和創(chuàng)新性的結(jié)構(gòu)吸引公眾的注意力。在圖一中展示的是兩個令人印象深刻的建筑，迄今為止最長的混凝土箱梁橋，陽光高架公路橋和休斯敦船舶航道橋。</p><p><b>　　中跨度</b></p><p>　

66、　中跨度包括50到200英尺的跨度，傳統(tǒng)上一般使用預(yù)應(yīng)力鋼筋和混凝土梁。未來，將會出現(xiàn)具備高性能特點的新材料，混凝土和鋼材料的強度也會得到加強，強度更高的材料和創(chuàng)新的設(shè)計理念集合在一起會產(chǎn)生更長的跨度，結(jié)果將會是有更少的子結(jié)構(gòu)的簡化結(jié)構(gòu)，和整體造價的降低。使用鋼筋混凝土組合的空間框架結(jié)構(gòu)會因為易于施工和相對低成本進(jìn)入這個市場。工程準(zhǔn)備，開箱即裝即用，橋梁預(yù)制構(gòu)件也會變的更加普遍，并且會開始挑戰(zhàn)個人設(shè)計，創(chuàng)新對中跨度橋梁會引起比其他兩種類

67、型更大的改變，在圖2中，一個明顯跨越了整個高速公路的創(chuàng)新性鋼橋梁，這樣的明確跨度巷道將會成為未來的熱門選擇。</p><p><b>　　小跨度</b></p><p>　　混凝土板、木材板、預(yù)應(yīng)力混凝土造型和軋制型鋼分享了目前跨度達(dá)到50英尺的橋梁市場。這些橋梁種類的挑戰(zhàn)將是大跨度涵洞和預(yù)工程，開箱即裝即用，橋梁預(yù)制構(gòu)件，圖3所展示的就是一種開始挑戰(zhàn)許多典型小跨度結(jié)

68、構(gòu)的典型大跨度涵洞。</p><p><b>　　設(shè)計</b></p><p>　　在二十世紀(jì)，通過標(biāo)準(zhǔn)的規(guī)范來設(shè)計橋梁已經(jīng)成為一種規(guī)則，這種情況會持續(xù)到下個世紀(jì)，然而，未來設(shè)計過程將會因為規(guī)范、荷載、檢驗和電腦化變得十分不同，</p><p><b>　　規(guī)范</b></p><p>　　在二十世

69、紀(jì)末，美國公路運輸協(xié)會用于橋梁結(jié)構(gòu)設(shè)計的荷載因素設(shè)計規(guī)范和荷載阻力因素設(shè)計規(guī)范分道揚鑣，荷載阻力因素設(shè)計規(guī)范近來正在被指定為未來設(shè)計的標(biāo)準(zhǔn)。荷載因素設(shè)計規(guī)范會繼續(xù)使用一段時間，但是隨著荷載阻力因素規(guī)范設(shè)計規(guī)范被更廣泛的接受，它的使用會逐漸減少。最終，荷載因素設(shè)計規(guī)范將會停用，而荷載阻力因素設(shè)計規(guī)范則會被全面通過，這將會被證明是正確的行動方針，美國公路運輸協(xié)會的荷載阻力因素規(guī)范將會隨著新的研究、新的設(shè)計理念和新的材料持續(xù)不斷演變，荷載阻力

70、因素設(shè)計方法將會被證明是高效的，并且會輕易的適用于各種建筑材料，包括鋼鐵、混凝土、木材和新的高強度塑料聚合物，荷載阻力因素設(shè)計因為兩個方面的原因：子結(jié)構(gòu)設(shè)計和電腦軟件，并不會被設(shè)計界輕易的接受。建立荷載阻力因素設(shè)計規(guī)范的一個目的是對從上部結(jié)構(gòu)到下部結(jié)構(gòu)的每個部分提供更高平均水平的可靠性。因為缺乏可接受的方法進(jìn)行基礎(chǔ)分析和設(shè)計，使用荷載阻力因素設(shè)計原理進(jìn)行下部結(jié)構(gòu)設(shè)計在數(shù)年內(nèi)尚不成熟，只有在更多的研究和完善規(guī)范后，下部結(jié)構(gòu)的這種情況才可能

71、得到改觀，荷載阻力因素設(shè)計代碼的廣泛運用將會被電腦軟件的缺乏而減緩進(jìn)程，荷載阻力因素設(shè)計代碼的詳細(xì)本質(zhì)需要設(shè)計者</p><p><b>　　荷載</b></p><p>　　荷載規(guī)范的核心是設(shè)計車輛荷載，從1944年沿用至今的老式的HS-20式卡車，作為一種與21世紀(jì)交通需求有關(guān)的交通工具正在被質(zhì)疑，本世紀(jì)初，兩個關(guān)于繼續(xù)使用這種車輛的具體問題會逐步出現(xiàn)，第一個問題

72、是一種不同的交通工具是否能更好的與來自路邊安裝的檢測系統(tǒng)的動態(tài)稱重的數(shù)據(jù)搭配。雖然這些數(shù)據(jù)的精確性值得懷疑，它們卻表明了明確的發(fā)展趨勢，那就是卡車的長度、重量和交通流量統(tǒng)計較HS-20卡車已經(jīng)顯著的增加了。第二個問題是無論另一種交通工具是否能簡化計算，不同的因素和荷載狀況曾經(jīng)被應(yīng)用到HS-20式卡車使之適合荷載阻力因素設(shè)計規(guī)范?？紤]到這兩個問題，一種新的“千年卡車”活載配置方法將會出現(xiàn)。在經(jīng)過大量的數(shù)據(jù)收集后，測試和監(jiān)控項目就會啟動。&

73、lt;/p><p><b>　　現(xiàn)場測試</b></p><p>　　為了幫助設(shè)計一種合適的交通工具，將會安裝一種更全面的動態(tài)稱重系統(tǒng)，因為這種設(shè)備的精確性上的先進(jìn)和耐久性，動態(tài)荷載數(shù)據(jù)將會和靜態(tài)荷載數(shù)據(jù)吻合，一副精確的圖片會描述出公路橋梁上的實際貨車軸重和軸間距。新出現(xiàn)的技術(shù)如傳感器和石英光纖技術(shù)的增強，還有壓電電纜，使更精確的數(shù)據(jù)收集成為可能，因為橋梁儀表數(shù)目的顯著增

74、加智能話橋梁會成為新千年的熱門訂單，實際盈利將會用十分類似于國家天氣預(yù)報追蹤每日溫度的方式被測量和追蹤，動態(tài)稱重的信息將會與儀表橋梁的信息聯(lián)系起來，高性能計算機的應(yīng)用是數(shù)據(jù)的大量分析成為可能，荷載阻力因素設(shè)計的荷載因素將會在新數(shù)據(jù)的基礎(chǔ)上更新，特別是鋼結(jié)構(gòu)能從儀器化和現(xiàn)場測試中獲益。作為對疲勞和相關(guān)問題的回應(yīng)，鋼橋?qū)b備儀表來測定失效機制，特別是大量荷載周期條件下的低應(yīng)力范圍內(nèi)的裂紋萌生。新興技術(shù)會導(dǎo)致這些關(guān)系的發(fā)現(xiàn)，并帶來設(shè)計方法的

75、革新，對造成疲勞的細(xì)節(jié)的具備成本效益的改造應(yīng)用會帶來那些有疲勞問題的橋梁的橋梁管理計劃的變革。鑒于這方面知識的增長，鋼橋多半會因為功能上的原因而不是結(jié)構(gòu)上的原因被替代。</p><p><b>　　分析</b></p><p>　　計算機程序能夠進(jìn)行的數(shù)據(jù)大量分析將會開發(fā)出被檢驗的核心設(shè)計參數(shù)如分布系數(shù)、多種存在因素和均布荷載。荷載傾向和結(jié)構(gòu)對這些荷載的應(yīng)答方式將會更

76、容易被預(yù)測。這將會導(dǎo)致設(shè)計參數(shù)和公式的簡化，并且會在完成設(shè)計計算速度方面帶來顯著的提高。二十一世紀(jì)的橋梁設(shè)計將會比二十世紀(jì)末更簡單、更精確。</p><p><b>　　設(shè)計工具</b></p><p>　　越來越多的國家將會在使用標(biāo)準(zhǔn)化細(xì)節(jié)方面進(jìn)行合作，在區(qū)域化的基礎(chǔ)上，計算機程序、起草細(xì)節(jié)和制作設(shè)計和計劃將會更加相似。這種標(biāo)準(zhǔn)化將會減少承包商和供應(yīng)商的建筑成本。速

77、度和精確性都會大大增加。單獨工作多年以后，計算機輔助工程和計算機起草將被成功的整合。設(shè)計和計劃將是迭代和互動的，并且計劃準(zhǔn)備極具成本效應(yīng)。自動規(guī)范檢查器和代碼核查員會通知設(shè)計工程師，使他們減少設(shè)計錯誤。更重要的是設(shè)計優(yōu)化將一鍵式解決。為了獲得專家的實時建議，人工智能將擴(kuò)大記憶儲存容量增多設(shè)計者選項。檢查精確性和可靠性設(shè)計軟件的專家系統(tǒng)的需求對橋梁設(shè)計專業(yè)人員來說是一個挑戰(zhàn)。當(dāng)然，與此相關(guān)的挑戰(zhàn)還有一直以來存在的關(guān)于職業(yè)責(zé)任的爭論。<

78、;/p><p><b>　　自動化</b></p><p>　　因特網(wǎng)和電子郵件將是設(shè)計者、制造者和承包商的標(biāo)準(zhǔn)通信方式。不同國家的設(shè)計師和起草者共同工作將變得更加常見。通訊將會更加電子化，消除打印和郵件往返的時間。承包商和制造者將見證電子化的最終計劃。</p><p><b>　　材料</b></p><

79、p>　　在橋梁工程的演化中，材料一直以來扮演了一個非常重要的角色。傳統(tǒng)材料如混凝土、鋼材和木材的加強將會繼續(xù)，但是最革命性的變化將發(fā)生在纖維增強塑料，高強度、高性能鋼材和混凝土，還有玻璃鋼和木材的混合方面。</p><p><b>　　纖維增強材料</b></p><p>　　今天，在橋梁建筑材料方面纖維增強塑料還處于初級階段。然而，玻璃鋼材料不同組合的進(jìn)一步實

80、驗將給簡單和復(fù)雜的橋梁結(jié)構(gòu)帶來創(chuàng)造性的持久的解決。玻璃鋼橋梁工程表明，這種材料在變形，材料延性，蠕變性，與混凝土和鋼材共同作用的反應(yīng)，和長時間暴露在紫外線和其他環(huán)境因素如水分、凍融、濕度、化學(xué)腐蝕的條件下存在固有的問題，為了幫助解決這些問題，將開發(fā)出材料實驗標(biāo)準(zhǔn)和設(shè)計方法來適應(yīng)玻璃鋼材料性能。國家一級的綜合性研究工作將要展開，使玻璃鋼成為一種可靠的、低維護(hù)的橋梁材料，能夠在職業(yè)設(shè)計師、建筑工程師合作完成的橋梁結(jié)構(gòu)提供一種令人滿意的性能。

81、橋梁業(yè)主將會使玻璃鋼成為一種可行的、有競爭力的替代傳統(tǒng)材料的橋梁施工材料。大學(xué)很有可能把他們的課程擴(kuò)大到在他們的課業(yè)中包括玻璃鋼和其他復(fù)合材料，使未來的橋梁專業(yè)人士接受并充分利用玻璃鋼。</p><p><b>　　高強度、高性能鋼材</b></p><p>　　不同于玻璃鋼，高強度鋼材更易于被橋梁工程師認(rèn)可。初步驗收取得了成果，因為新的鋼鐵材料使減少結(jié)構(gòu)荷載成為可能

82、。高強度鋼鐵材料將會被更廣泛的接受因為他們被增強的材料性能。在提高材料的韌性和高強度鋼的焊接性方面取得的成果將擴(kuò)大到所有等級的鋼材。為了處理諸如焊接性、韌性、制造和結(jié)構(gòu)性能之類的材料特性，設(shè)計規(guī)格將持續(xù)更新。今天的高性能鋼鐵材料將成為未來建設(shè)結(jié)構(gòu)的標(biāo)準(zhǔn)。橋梁類型上的結(jié)構(gòu)和實驗上的進(jìn)展，如空間框架和創(chuàng)新性復(fù)合結(jié)構(gòu)，將導(dǎo)致鋼材料的進(jìn)一步優(yōu)化。對未來的橋梁結(jié)構(gòu)來說，高強度復(fù)合玻璃鋼有著巨大的潛力。在新千年里高性能鋼筋變的非常普遍，以鋼鐵為核心

83、的復(fù)合鋼筋，不銹鋼介質(zhì)包層和其他復(fù)合型材料將會在混凝土結(jié)構(gòu)中獲得廣泛的接受。與高性能材料在橋面的使用相結(jié)合，這種結(jié)構(gòu)的平均壽命將會接近以前建造的類似結(jié)構(gòu)的兩倍，未來需要生命周期成本分析的國家政策，將對進(jìn)一步的發(fā)展和使用在橋面使用創(chuàng)新性材料方面，提供一個巨大的激勵</p><p><b>　　高性能混凝土</b></p><p>　　作為公路研究計劃戰(zhàn)略的研究和公路管理

84、局努力推行，高性能混凝土正在變成傳統(tǒng)橋梁建筑材料，對在職工程師來說，強度和滲透率誰是長期耐久性高性能混凝土的主要指標(biāo)的爭論竟會繼續(xù)，然而，過去的案例研究清楚的表明，對滲透試驗作為長期混凝土耐久性指標(biāo)的需要。因為高性能混凝土具有良好的耐久的和強度特性，使它成為一種多功能材料，前途光明。目前，因為質(zhì)量控制和質(zhì)量保證的問題，妨礙了基于性能的規(guī)范的使用，長期耐久性評估是一種事后的考慮?？茖W(xué)家和工程師最終將會開發(fā)出一種裝置，通過瞬間測試未硬化狀態(tài)

85、的混凝土來瞬間預(yù)計硬化狀態(tài)的混凝土的長期耐久特性。</p><p><b>　　木材</b></p><p>　　強化木材的新流程將會得到繼續(xù)發(fā)展，包括膠合木的組合和玻璃鋼的結(jié)合。這個概念類似于鋼筋混凝土，木材抵抗壓縮荷載，玻璃鋼抵抗拉伸荷載。這個概念將被廣泛應(yīng)用于未來的木結(jié)構(gòu)中。這種技術(shù)的優(yōu)點在于彎矩控制設(shè)計的區(qū)域（當(dāng)使用低級別木頭時）。玻璃鋼加固大大增強了橫梁的拉

86、伸能力，這將使低級別的木材使用在很多結(jié)構(gòu)中十分經(jīng)濟(jì)，這種新型復(fù)合材料也可以被用在最小空隙成問題的地方，在木材防腐劑領(lǐng)域的突破將繼續(xù)下去，他們將導(dǎo)致新的將環(huán)保方面的使用、應(yīng)用和木材處理結(jié)合起來的替代工藝和程序的發(fā)展和完善。</p><p><b>　　其他材料</b></p><p>　　一個建造業(yè)未來的挑戰(zhàn)將會是將再生材料（包括塑料），副產(chǎn)品和廢品摻入道常規(guī)和高強度混

87、凝土建筑材料中去。未來的環(huán)保法規(guī)和棄置廢品的空間的缺乏將會使這個問題成為重中之重。大量的時間和財政資源將被用來把可循環(huán)材料發(fā)展成為適用的建筑材料產(chǎn)品。</p><p><b>　　審美考量</b></p><p><b>　　公眾參與</b></p><p>　　近年來在設(shè)計過程中公眾參與的增長是因為公眾想要被更好的美學(xué)處

88、理的橋梁，特別是被考慮最為附近地標(biāo)的橋梁，在未來公眾參與將會繼續(xù)并且將會更多。為了促進(jìn)這一進(jìn)程，工程師將實施使用三維可視技術(shù)，公眾將可以在聽證會或者互聯(lián)網(wǎng)上查看和評論。</p><p><b>　　互動設(shè)計</b></p><p>　　將公眾意見納入計劃，將要求最后一分鐘的變化很容易的加入設(shè)計和起草過程，自動調(diào)節(jié)設(shè)計和生成計劃的電腦設(shè)計和起草方案將可以快速修改，適應(yīng)這

89、項技術(shù)將需要最新的工程分析技巧，對靈活設(shè)計的強調(diào)無疑需要工程師們加強他們的美學(xué)設(shè)計技能和綜合的交流技巧。</p><p><b>　　審美過程</b></p><p>　　結(jié)構(gòu)的審美將變得非常普遍，只有那些最偏遠(yuǎn)的地區(qū)會不受影響。幾乎所有的橋梁都將有一個詳細(xì)的審美處理，或者至少是一個審美審查。額外的規(guī)劃時間和設(shè)計時間將被作為結(jié)構(gòu)成本的一部分而被接納。公眾的關(guān)注程度將在