橋梁工程PPT(姚林森第二版)第3篇第5章

1、第三篇 懸臂與連續(xù)體系梁橋第5章 施工方法簡介Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology本章內(nèi)容 5.1 有支架澆筑施工法 5.2 平衡懸臂施工方法 5.3 逐跨頂推施工方法 5.4 移動模架施工法 Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.1 有支架澆筑施工法Dept of Road & Bridge Engin

2、eering, School of Transportation, Wuhan University of Technology(1)支架和模板支架按構(gòu)造可分為： 支柱式 梁式 梁柱式按材料可分為： 木支架 鋼支架 鋼木混合 萬能桿件拼裝A 支架的分類知識點(diǎn)：有支架澆筑施工法有支架澆筑施工法，開始講解這個(gè)知識點(diǎn)5.1 有支架澆筑施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.1 有支架澆筑施工法Dept of Road & Bridge Enginee

3、ring, School of Transportation, Wuhan University of TechnologyB 對支架的要求l支架雖然是臨時(shí)結(jié)構(gòu)，但它要承受橋梁的大部分恒重，因此必須有足 夠的強(qiáng)度、剛度，保證就地澆筑的順利進(jìn)行。支架的基礎(chǔ)要可靠，構(gòu)件結(jié)合緊密并加入縱、橫向連接桿件，使支架成為整體。l在河道中施工的支架要充分考慮洪水和漂浮物的影響。l支架在受荷后有變形和撓度，在安裝前要進(jìn)行計(jì)算，并設(shè)置預(yù)拱度，使結(jié)構(gòu)的外形尺寸和標(biāo)高符合設(shè)計(jì)要求。l支架上要設(shè)置落架設(shè)備，落架時(shí)要對稱、均勻，不應(yīng)使主梁發(fā)生局部受力的狀態(tài)。5.1 有支架澆筑施工法Dept of Road & Bridg

4、e Engineering, School of Transportation, Wuhan University of Technology（1）作用在支架上的荷載有橋跨結(jié)構(gòu)的重力，澆筑設(shè)備的重力（包括振動荷載），風(fēng)力及施工人員的重力，連同模板和支架自重均由支架承受。（2）支架的各構(gòu)件應(yīng)按其計(jì)算圖式進(jìn)行強(qiáng)度計(jì)算，容許應(yīng)力可按臨時(shí)結(jié)構(gòu)予以提高。（3）支架的撓度需要演算，并小于其容許值。（4）支架的預(yù)拱度計(jì)算包括梁自重所產(chǎn)生的撓度，支架受載后產(chǎn)生的彈性變形和非彈性變形，支架基礎(chǔ)的沉降量等。（5）支架卸架設(shè)備的選用及受力計(jì)算。C 支架的計(jì)算要點(diǎn)：5.1 有支架澆筑施工法Dept of Road &

5、 Bridge Engineering, School of Transportation, Wuhan University of TechnologyD 常用模板可分為木模板和鋼模板： 木模板可按結(jié)構(gòu)要求預(yù)制，在支架上拼裝。 鋼模板做成大型塊件，由加勁骨架焊接而成。5.1 有支架澆筑施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.1 有支架澆筑施工法Dept of Road & Bridge Engineering, School of Trans

6、portation, Wuhan University of Technology（2）就地澆筑施工法 連續(xù)施工期間保證混凝土整體性； 懸臂和連續(xù)體系橋梁一般要分層或分段進(jìn)行； 澆筑時(shí)保證一定的速度，上層澆筑應(yīng)在下層混凝土初凝前完成； 施工中必須消除支架沉降不均導(dǎo)致的裂縫澆筑順序應(yīng)使支架沉降均勻發(fā)展。5.1 有支架澆筑施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology澆筑次序和工作縫設(shè)置5.1 有支架澆筑施工法Dept of Road & Bridge En

7、gineering, School of Transportation, Wuhan University of Technology（3）養(yǎng)護(hù)和落架 n 澆筑后應(yīng)對混凝土進(jìn)行養(yǎng)護(hù)，促使其硬化；n 防止混凝土受雨淋、日曬、受凍及荷載震動和沖擊；n 預(yù)應(yīng)力混凝土連續(xù)梁橋在預(yù)應(yīng)力筋張拉后恒載自重已能由梁本身承擔(dān)時(shí)再落架。知識點(diǎn)：有支架澆筑施工法有支架澆筑施工法，講解結(jié)束本章內(nèi)容 5.1 有支架澆筑施工法 5.2 平衡懸臂施工方法 5.3 逐跨頂推施工方法 5.4 移動模架施工法 Dept of Road & Bridge Engineering, School of Transportation,

8、 Wuhan University of Technology5.2 平衡懸臂施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology（1）懸臂施工關(guān)鍵v在施工過程中必須保證墩與梁固結(jié) 用懸臂施工法從橋墩兩側(cè)逐段延伸來建造預(yù)應(yīng)力混凝土懸臂梁橋時(shí)，為了承受施工過程中可能出現(xiàn)的不平衡力矩，保證施工過程中結(jié)構(gòu)的穩(wěn)定可靠，需要采取措施使墩頂?shù)牧闾枆K件與橋墩臨時(shí)固結(jié)起來。v 必須充分考慮施工期出現(xiàn)的體系轉(zhuǎn)換問題。 結(jié)構(gòu)體系轉(zhuǎn)換是指在施工過程中，當(dāng)某一施工程序完成后，橋梁結(jié)構(gòu)

9、的受力體系發(fā)生了變化，這種變化過程簡稱為體系轉(zhuǎn)換。知識點(diǎn)：平衡懸臂施工法平衡懸臂施工法，開始講解這個(gè)知識點(diǎn)Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法Dept of Road & Bridge Engineering, School o

10、f Transportation, Wuhan University of Technology5.2 平衡懸臂施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法懸臂法建造連續(xù)梁橋的體系轉(zhuǎn)換Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法（2）懸臂施工分類懸臂澆筑法l懸臂澆筑法是利用

11、懸吊式活動腳手架（掛籃）在墩柱兩側(cè)對稱平衡地澆筑梁段混凝土，達(dá)到規(guī)定強(qiáng)度后張拉預(yù)應(yīng)力筋并錨固，然后移動掛籃進(jìn)行下一段施工，直到懸臂端為止。Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法1-底模架 2、3、4-懸吊系統(tǒng) 5-承重結(jié)構(gòu) 6-行走系統(tǒng) 7-平衡重 8-錨固系統(tǒng) 9-工作平臺Dept of Road & Bridge Engineering, School of Transportation, Wuhan University o

12、f Technology5.2 平衡懸臂施工法斜拉式掛籃簡圖Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法墩側(cè)頭幾對梁段的澆筑Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法 箱形梁段工藝流程：移掛籃裝底、側(cè)模裝底、肋板鋼筋和預(yù)留管道裝內(nèi)模裝頂板鋼筋和預(yù)留管道澆筑混凝土養(yǎng)生預(yù)留應(yīng)力筋、

13、張拉和錨固管道壓漿Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法 不需占地較大的預(yù)制場； 易于調(diào)整和控制梁段的位置； 整體性好； 不需要大型機(jī)械設(shè)備； 施工不受氣候條件影響； 需要施工人員少，技術(shù)熟練快，工作效率高。懸臂澆筑法的優(yōu)點(diǎn)：Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法懸臂

14、拼裝法懸臂拼裝法施工是在工廠或橋位附近沿軸線劃分成適當(dāng)?shù)膲K件進(jìn)行預(yù)制，然后用船或平板車運(yùn)至架設(shè)點(diǎn)，用活動吊機(jī)等吊起后向墩柱兩側(cè)對稱均衡的拼裝就位，張拉預(yù)應(yīng)力筋，重復(fù)作業(yè)至拼裝完懸臂梁。Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法通常使用間隔澆筑法來預(yù)制塊件預(yù)制塊件（間隔法）Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Te

15、chnology5.2 平衡懸臂施工法桁式吊懸臂拼裝施工Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法懸臂閘門式吊機(jī)懸臂拼裝施工Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法預(yù)制塊件間接縫處理分為濕接縫、干接縫和半干接縫等接縫形式知識點(diǎn)：平衡懸臂施工法平衡懸臂施工法，講解結(jié)束本章內(nèi)容

16、 5.1 有支架澆筑施工法 5.2 平衡懸臂施工方法 5.3 逐跨頂推施工方法 5.4 移動模架施工法 Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of TechnologyDept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法（1）施工臨時(shí)設(shè)施v導(dǎo)梁：設(shè)置在主梁的前端，為等截面或變截面的鋼桁梁或鋼板梁， 主梁前端裝有預(yù)埋件與鋼導(dǎo)梁栓接

17、。v臨時(shí)墩：目前在大跨徑內(nèi)最多設(shè)兩個(gè)臨時(shí)墩。v拉索、托架及斜拉索：拉索系統(tǒng)由鋼制塔架、連接構(gòu)件、豎向千斤頂和鋼索組成。知識點(diǎn)：逐跨頂推施工法逐跨頂推施工法，開始講解這個(gè)知識點(diǎn)Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法頂推法施工的基本工序：在預(yù)制場中集中制作23段等高度箱形梁段（1030m一段）；在上、下翼板內(nèi)施加能承受施工中變號內(nèi)力的預(yù)應(yīng)力；用頂推設(shè)備將支承在氟塑料板與不銹鋼滑到上的箱梁向前推移；推出一段再接長一段，反復(fù)操作。（2）頂

18、推施工作業(yè)Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法連續(xù)梁頂推法施工示意圖a）單向單點(diǎn)頂推 b）按每聯(lián)多點(diǎn)頂推 c）雙向頂推1-預(yù)制場 2-梁段 3-導(dǎo)梁 4-千斤頂裝置 5-滑道支承 6-臨時(shí)墩 7-已架完的梁 8-平衡重Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法（3）主要

19、頂推設(shè)備頂推施工中采用的主要設(shè)備是千斤頂和滑道。頂推工藝有推頭式和拉桿式兩種。Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法推頭式頂推裝置：Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法拉桿式頂推裝置：Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.3 逐跨頂推施工法滑道構(gòu)造：知識點(diǎn)：逐跨頂推施工法逐跨頂推施工法，講解結(jié)束本章內(nèi)容 5.1 有支架澆筑施工法 5.2 平衡懸臂施工方法 5.3 逐跨頂推施工方法 5.4 移動模架施工法 Dept of Road & Bridge Engineeri