2.斜井總體施工方案
2.1選擇位置依據(jù)
⑴增加斜井后能確實(shí)有效地縮短工期。
⑵有較好的施工用水、用電等外部環(huán)境。
⑶有較好的施工條件、場(chǎng)地及棄渣用地。
⑷設(shè)置斜井的位置盡量少占用場(chǎng)地，避免拆遷。
⑸斜井的選線盡量避免房屋建筑，以減少施工干擾。
⑹經(jīng)濟(jì)合理的原則。
基于以上原則，對(duì)xx隧道全線進(jìn)行了詳細(xì)的勘察、對(duì)比，最終決定將斜井進(jìn)洞位置選擇在DK283+700右側(cè)一破舊土房處。但此處埋深較淺，且上部土體均為堆積土，一旦斜井施工，可能會(huì)引起周圍土體滑坍，威脅周圍居民區(qū)安全。
2.2 總體方案
斜井施工進(jìn)洞前有一55米埋深較淺段采用長(zhǎng)拉槽開挖，開挖后采用C20砼重力式擋墻支護(hù)，擋墻墻高2～6米；同時(shí)對(duì)暗挖段地表進(jìn)行注漿加固，然后采用超前管棚進(jìn)洞。斜井進(jìn)洞后采用臺(tái)階法施工，遵循短開挖、弱爆破、強(qiáng)支護(hù)、快封閉、早成環(huán)的原則。斜井施工至與正洞交界后，在正洞左側(cè)邊墻與橫洞交界里程處，以組合焊接一起的3榀I20b鋼架作為基礎(chǔ)，在此型鋼鋼架上焊接3榀I20b型鋼橫梁，為正洞鋼架提供落腳平臺(tái)；同時(shí)以圓曲線形式轉(zhuǎn)體進(jìn)入正洞，同時(shí)上坡開挖至正洞拱頂高程，并繼續(xù)沿相同方向掘進(jìn)15米（此段設(shè)置臨時(shí)支護(hù)，采用拱墻I20b工字鋼）；形成作業(yè)空間后，轉(zhuǎn)向相反方向施工，擴(kuò)挖臨時(shí)支護(hù)達(dá)到正洞標(biāo)準(zhǔn)斷面，然后同時(shí)向出口施工。
目 錄
1.工程概況 .................................................................................................................2
2.總體施工方案...........................................................................................................2
2.1位置選擇依據(jù)........................................................................................................2
2.2總體方案................................................................................................................2
3.主要參數(shù)及工程數(shù)量...............................................................................................3
3.1洞身參數(shù)................................................................................................................3
3.2支護(hù)參數(shù)……………………………....................................................................4
3.3主要工程數(shù)量………………………....................................................................5
4.施工總體布置...........................................................................................................5
4.1臨時(shí)工程................................................................................................................5
4.2施工場(chǎng)地布置........................................................................................................6
4.3工期目標(biāo)................................................................................................................7
4.4人員安排................................................................................................................7
4.5機(jī)械設(shè)備................................................................................................................8
5施工方法...................................................................................................................8
5.1洞口段施工............................................................................................................8
5.2超前支護(hù)................................................................................................................8
5.2.1小導(dǎo)管施工.........................................................................................................9
5.3斜井洞身施工........................................................................................................9
5.3.1斜井排水...........................................................................................................10
5.3.2噴射砼...............................................................................................................10
5.3.3注漿...................................................................................................................10
5.3.4掛鋼筋網(wǎng)...........................................................................................................11
5.3.5安I16工字鋼.................................................................................................11
5.5斜井轉(zhuǎn)正洞施工..................................................................................................11
5.4仰拱與二襯施工..................................................................................................11
6.監(jiān)控量測(cè).................................................................................................................12
7.地質(zhì)超前預(yù)報(bào).........................................................................................................12
8.施工安全技術(shù)措施.................................................................................................13
9.施工質(zhì)量技術(shù)措施.................................................................................................13
新正陽(yáng)隧道斜井平面圖