【正文】 第一篇：畢業(yè)設(shè)計(jì)混凝土橋梁結(jié)構(gòu)形式(中英文翻譯)混凝土梁橋的結(jié)構(gòu)形式事實(shí)證明，預(yù)應(yīng)力混凝土結(jié)構(gòu)是在技術(shù)上先進(jìn)、經(jīng)濟(jì)上有競(jìng)爭(zhēng)力、符合審美學(xué)的一種先進(jìn)技術(shù)。從使用標(biāo)準(zhǔn)組成的小跨徑橋梁到吊梁和跨徑將近100英尺的連續(xù)箱梁橋，幾乎所有的混凝土橋梁，甚至于相對(duì)短時(shí)間的橋梁都是預(yù)應(yīng)力結(jié)構(gòu)的。采用預(yù)制、現(xiàn)場(chǎng)澆筑或兩種方法并用。在同一工程中經(jīng)常同時(shí)使用先張法和后張法。在美國，公路橋一般情況下必須滿足荷載、設(shè)計(jì)和AASHTO規(guī)定的建設(shè)的要求。對(duì)于服務(wù)于其它目的步行街和橋梁的設(shè)計(jì)要求由當(dāng)?shù)氐幕虻胤降拇a建立。ACI代碼的備注也被納入?yún)⒖?。伴隨最小交通中斷的大約100英尺的跨徑的橋梁由提供低的初級(jí)預(yù)算，最小量維修和養(yǎng)護(hù)費(fèi)用和快速的簡(jiǎn)易的預(yù)制板組成。這種梁一般是用先張法。預(yù)制板一塊挨一塊的放置并且在相鄰的預(yù)制板間受剪的縫隙填滿不收縮的灰泥之后，經(jīng)常在中間橫膈膜的位置后張拉。對(duì)于公路，用瀝青鋪設(shè)的表面可以直接用在預(yù)制混凝土的上面。在某些情況下，一塊放置在正確位置的現(xiàn)澆板提供復(fù)合作用?？招陌逡话阌糜谏疃?5英尺到21英尺，寬度3英尺或4英尺。對(duì)于一個(gè)標(biāo)準(zhǔn)HS20的公路，空心板適合于大約50 英尺的跨徑。標(biāo)準(zhǔn)渠化區(qū)段在多種寬度，深度從21英尺到35英尺時(shí)是有利的，可用于大約20英尺到60英尺的跨徑。中空的箱形梁和T形梁用于大約100英尺的長跨徑。對(duì)于中等跨徑的大約120英尺的公路橋，一般使用AASHTO 標(biāo)準(zhǔn)梁。它們和一種復(fù)合現(xiàn)場(chǎng)預(yù)制行車道板一起使用。在板被安置之后，這樣的梁經(jīng)常在預(yù)澆梁的先張拉 與合成梁的后張拉后結(jié)合。試圖獲得改進(jìn)經(jīng)濟(jì)，一些國家已經(jīng)采用更精煉的設(shè)計(jì)，例如華盛頓州標(biāo)準(zhǔn)梁。經(jīng)過特別設(shè)計(jì)預(yù)制建筑梁可以用來攜帶一個(gè)單軌鐵路系統(tǒng)。完成的沃爾特迪斯尼樂園單軌鐵路的一系列的特征, 每個(gè)包括六個(gè)單獨(dú)支持的預(yù)拉梁，一起形成連續(xù)結(jié)構(gòu)。典型的跨距是100到110英尺。被使用的337根梁，大約一半有垂直與水平曲率和易變超級(jí)升高的一些結(jié)合。所有的梁是中空的，它的特征是通過在曲梁中插入泡沫和在直梁制作中移動(dòng)形心軸獲得。由于運(yùn)輸問題和構(gòu)件垂直的大而重的問題，預(yù)制梁不能用于跨徑超過120英尺的橋梁。另一方面，橋梁有一種向大跨徑發(fā)展的明顯趨勢(shì)。對(duì)于提高的都市高速道路來說，大跨徑促進(jìn)通路而且將對(duì)下面的活動(dòng)妨礙減到最少。對(duì)環(huán)境的損害問題的關(guān)心，導(dǎo)致連續(xù)高架橋大跨徑的選擇。對(duì)于跨河橋，因?yàn)楹叫虚g隙的需求，中間可能不可以搭設(shè)橋墩。在這一個(gè)類型的典型建筑中，橋墩（臺(tái)）采用現(xiàn)場(chǎng)預(yù)制, 經(jīng)常使用滑動(dòng)的技術(shù)。一個(gè)箱梁的“ 錘頭”澆筑在橋墩的頂端, 并且通過平衡的懸臂方法控制每個(gè)方向的建筑進(jìn)行。最后,在完成跨中結(jié)合處的澆筑之后, 這種結(jié)構(gòu)對(duì)于完全連續(xù)性的橋梁來說是進(jìn)一步的受拉的。修剪鑰匙可能被用在片段之間垂直面之上, 而且預(yù)制建筑與環(huán)氧基樹脂黏在一起。想象的工程學(xué)藉著許多特別的技術(shù)示范已經(jīng)延長混凝土建筑的范圍，就橋梁而言，已經(jīng)遠(yuǎn)遠(yuǎn)超過幾年以前可以想象的到的任何事。在美國，雙向彎曲的現(xiàn)場(chǎng)澆鑄的部分箱梁已經(jīng)成功地完成 310 英尺 的跨距，跨越了北加州的鰻魚河。該橋的中間跨度550英尺，側(cè)跨跨度390英尺，初步設(shè)計(jì)已經(jīng)完成。預(yù)應(yīng)力混凝土橋梁很適合于大跨徑的另一種形式是懸索箱梁。一個(gè)值得注意的例子是阿根廷境內(nèi)的ChacoCorrientes橋。橋的主跨徑804英尺，由兩個(gè)A型構(gòu)架塔支撐，懸索從塔頂?shù)窖刂装迳煺?。受拉的懸索不僅提供一種垂直反應(yīng)組成支撐底板，而且對(duì)于箱梁產(chǎn)生水平的壓縮，增加構(gòu)件中的張拉力。許多年以前德國工程師 Ulrich Finsterwalder 提出適合于負(fù)擔(dān)荷載和大跨徑的一個(gè)結(jié)構(gòu)類型是壓帶式橋。壓帶是橋運(yùn)輸跨越萊茵河的一個(gè)管道和人行道，跨徑446英尺。上部結(jié)構(gòu)的施工順序是（a）垂直的一對(duì)懸索，(b)在每個(gè)懸索的下面，安置預(yù)制板形成一人行道甲板和 一U型 的平臺(tái), 并且(c)在附近現(xiàn)場(chǎng)澆注混凝土。放置在頂部的管道支撐在扶手的頂部，向一邊傾斜，大幅地增加結(jié)構(gòu)的主要風(fēng)速。討論橋梁形式應(yīng)適當(dāng)?shù)目紤]結(jié)構(gòu)的美學(xué)。當(dāng)結(jié)構(gòu)可能根據(jù)最小的費(fèi)用和技術(shù)設(shè)計(jì)的時(shí)候，時(shí)間消逝了。特別是橋梁結(jié)構(gòu)到處可見。生產(chǎn)視覺上不愉快的結(jié)構(gòu) , 過去經(jīng)常發(fā)生, 是一種不負(fù)專業(yè)責(zé)任的行為。特別地對(duì)于主要的跨距，還有一些比較普通的結(jié)構(gòu)來說，應(yīng)該在設(shè)計(jì)過程的概念階段尋找建筑的建議。出處：安瑞克．混凝土橋梁結(jié)構(gòu)形式[J]．建筑實(shí)錄(美)，2010，33(36)：34—36The Structure of Concrete Bridge Prestressed concrete has proved to be technically advantageous, economically petitive, and esthetically superior bridges, from very short span structures using standard ponents to cablestayed girders and continuous box girders with clear spans of nearly all concrete bridges, even those of relatively short span, are now , castinplace construction, or a bination of the two methods may be pretensioning and post tensioning are employed, often on the same the United States, highway bridges generally mustmeet loading ,design ,and construction requirements of the AASHTO requirements for pedestrian crossings and bridges serving other purposes may be established by local or regional codes and Code provisions are often incorporated by spans to about 100ft often consist of precast integraldeck units ,which offer low initial cost ,minimum ,maintenance ,and fast easy construction ,with minimum traffic girders are generally units are placed side by side ,and are often posttensioned laterally at intermediate diaphragm locations ,after which shear keys between adjacent units are filled with nonshrinking highway spans ,an asphalt wearing surface may be applied directly to the top of the precast some cases ,a castinplace slab is placed to provide posite voided slabs are monly available in depths from 15 to 21 widths of 3 to 4 a standard highway HS20 loading, they are suitable for spans to about 50 ft, Standard channel sections are available in depths from 21 to 35 in a variety of widths, and are used for spans between about 20 and 60 hollow box beamsand singletee girders are intended for longer spans up to about 100 mediumspan highway bridges ,to about 120 ft ,AASHTO standard I beams aregenerally are intended for use with a posite castinplace roadway girders often bine pretensioning of the precast member with posttensioning of the posite beam after the deck is an effort to obtain improved economy ,some states have adopted more refined designs ,such as the State of Washington standard specially designed precast girders may be used to carry a monorail transit finished guide way of Walt Disney World Monorail features a series of segments, each consisting of six simply supported pretensioned beams ,together to from a continuous spans are 100 to 110 half of the 337 beams used have some bination of vertical and horizontal curvatures and variable super beams are hollow, a feature achieved by inserting a styrofoam void in the curved beams and by a moving mandrel in straight beam girders may not be used for spans much in excess of 120 ft because of the problems of transporting and erecting large, heavy the other hand ,there is a clear trend toward the use of longer spans for elevated urban expressways ,long spans facilitate access and minimize obstruction to activities for environmental damage has led to the choice of long spans for continuous river crossings, intermediate piers may be impossible because of requirements of navigational typical construction of this type, piers are castinplace, often using the slipforming ―hammerhead‖ section of box girder is often cast at the top of the pier, and construction proceeds in each direction by the balanced cantilever , after the closing castinplace joint is made at midspan, the structure is further posttensioned for full keys may be used on the vertical faces between segments, and precast are glued with epoxy imaginative engineering demonstrated by many special techniques has extended the range of concrete construction for bridges far beyond anything that could be conceived just a few years the United States, twin curved castin –place segmental box girders have recently been pleted for of span of 310 ft over the Eel River in northern design has been pleted for twin continuous box girders consisting of central 550 ft spans flanked by 390 ft side form of prestressed concrete bridge well suited to long spans is the cablestayed box notable example is the ChacoCorrientes Bridge in bridges main span of 804 ft is supported by two Aframe towers, with cable s