目录一、工程概 ................................................................................................................... 2二、洞口段地质状况 ................................................................................................... 2三、施工方案 ............................................................................................................... 3四、施工方法及步骤 ................................................................................................... 41、截水沟施工 ...................................................................................................... 4（1）施工工艺流程 ....................................................................................... 4（2）工序分述 ............................................................................................... 42、明洞开挖及边、仰坡开挖与边、仰坡支护 .................................................. 6（1）、明洞及边、仰坡开挖 ......................................................................... 6（2）边、仰坡支护 ....................................................................................... 73、大管棚施工 ...................................................................................................... 8（1）导向墙套拱施工 ................................................................................... 8（2）搭设钻孔作业平台及安装钻机 ........................................................... 9（3）钻孔 ....................................................................................................... 9（4）清孔验孔 ............................................................................................. 11 （5）钢管加工及安装 ................................................................................. 12 （6）地层注浆 ............................................................................................. 12 4、明洞及洞门施工 ....................................................
