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(jiǎn)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(dòng)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 &

2、Bridge Engineering, 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(wàn)能桿件拼裝A 支架的分類知識(shí)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(shí)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

3、& Bridge Engineering, School of Transportation, Wuhan University of TechnologyB 對(duì)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(duì)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

4、Dept of Road & Bridge 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(dòng)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.

5、1 有支架澆筑施工法Dept of Road & 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 &

6、 Bridge Engineering, School of Transportation, 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

7、作縫設(shè)置5.1 有支架澆筑施工法Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology（3）養(yǎng)護(hù)和落架 n 澆筑后應(yīng)對(duì)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(dòng)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(shí)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(dòng)模架施工法 Dept of Road &am

8、p; 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 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(lái)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?hào)塊件與橋墩臨時(shí)固結(jié)起來(lái)。

9、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)的受力體系發(fā)生了變化，這種變化過程簡(jiǎn)稱為體系轉(zhuǎn)換。知識(shí)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(shí)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 Tech

10、nology5.2 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 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 Transpor

11、tation, 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懸臂澆筑法是利用懸吊式活動(dòng)腳手架（掛籃）在墩柱兩側(cè)對(duì)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(dòng)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(tái)Dep

12、t of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法斜拉式掛籃簡(jiǎn)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(duì)梁段的澆筑Dept of Road & Bridge Engineering, School of Transportation, Wuhan Uni

13、versity 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、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(chǎng)； 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

14、 & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 平衡懸臂施工法懸臂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(dòng)吊機(jī)等吊起后向墩柱兩側(cè)對(duì)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

15、澆筑法來(lái)預(yù)制塊件預(yù)制塊件（間隔法）Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technology5.2 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

16、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(shí)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 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(dòng)模架施工法 Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of TechnologyDept of Road & Bridge Engineering, Sc

17、hool 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。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(shí)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(shí)點(diǎn)Dept of Road & Bridge Engineering, School of Transportation, Wuhan University of Technolo

18、gy5.3 逐跨頂推施工法頂推法施工的基本工序：在預(yù)制場(chǎng)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(hào)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(zhǎng)一段，反復(fù)操作。（2）頂推施工作業(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(chǎng) 2-梁段 3-導(dǎo)梁 4-千斤頂裝置 5-滑道支

19、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 &a

20、mp; 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(shí)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(dòng)模架施工法 Dept of Road & Bridge Engineer