南水北调中线古运河枢纽的高边坡土钉防护

南水北调中线古运河枢纽的明挖段和暗挖段分界点设在石太高速公路19.20m高差的砂质高边坡坡脚以内,给分界点明挖段的基坑开挖和混凝土结构施工带来难题。施工方根据地质和边坡状况,对边坡实施＂倒梯形＂的注浆土钉布置与钢筋网锚喷混凝土支护。监测发现,边坡坡顶最大沉陷32mm,施工过程边坡稳定,既保证了暗涵结构施工安全,又保证石太高速公路正常运行,该项工程实践是一次有益的尝试。对同类工程建设有参考意义。

Soil-Nailing Protection for High Slope on the Ancient Canal Junction in the Middle Route of the South-to-North Water Transfer Project

The demarcation line between the open-cut section and tunneling section on the Ancient Canal Junction in the Middle Route of South-to-North Water Transfer Project is located in slope base of sandy high slope at 19. 20 m (height difference) of Shijiazhuang-Taiyuan Expressway, which brings some troubles to excavation of foundation pits and construction of concrete structures in the open-cut section. According to geolog-ical and slope condition,we has applied the inverted-ladder-shaped soil nailing layout and reinforcing fabric gunited concrete to the slope for sup-porting. The findings have showed that, with maximum subsidence 32rnm, slope is stable during construction, which not only ensures the con-struction safety of buried culverts but also keeps routine operation of Shijiazhuang-Taiyuan Expressway. The practice is a beneficial attempt for similar projects.