偏压隧道边坡稳定性分析与治理

Construction Technology of Bridge-Tunnel Connection Project

新建黔张常铁路安子村隧道DK67+980～DK68+110段地形属单面坡,线路左侧沟谷深切,洞身处于浅埋偏压状态。隧道施工至此段拱顶塌方,地表塌陷。研究了偏压隧道边坡稳定性分析方法与有效治理措施,保证了隧道施工安全。

As a form of connection between bridges and tunnels,the Bridge-Tunnel Connection has the objective situation of mutual interference due to the limitation of the tunnel entrance site and the bridge abutment extending into the tunnel,which further increases the construction difficulty and security risks of the project. In addition,the bridge abutment construction will lead to unstable foundation of tunnel portal structure. Therefore,the lining of tunnel portal section should be strengthened by arch shell structure + pile foundation crown beam to ensure the stability of tunnel portal structure. The Bridge-Tunnel Connection section involves many complicated processes,such as pile foundation,crown beam,retaining wall,abutment,open tunnel and drainage connection of bridge and tunnel. The limited site needs to organize a number of construction tasks,which brings great inconvenience to the construction organization. Therefore,reasonable construction organization and strict quality control are particularly important.