京珠高速公路小塘至甘塘段煤系地层路堑高边坡稳定性分析与防治

Stability analysis and control of cutting high slopes in coal measure strata along Xiaotang-Gantang of Beijing-Zhuhai expressway

京珠高速公路粤境小塘至甘塘段20m以上高度的煤系地层路堑边坡共计11处。岩层以全—强风化层为主,厚度20～40m,其物理力学性质大大降低,边坡可能发生平面破坏和圆弧破坏等2种破坏模式。部分地下水水质中SO2-4含量大于200mg l,具有强烈的硫酸盐侵蚀性。边坡防治对策应在详细勘察工程地质、水文地质的基础上,合理选用设置山坡截水沟、平台截水沟、泄水洞、边坡渗沟、排水仰孔等防、排水措施,减少地表水渗入坡体,疏干边坡表层地下水。

There are 11 artificial slopes above 20m high in the coal measure strata along XiaotangGantang section of BeijingZhuhai expressway. The strata of slopes are all overstrong weathered, 20～40m in thickness, and are of lower physical mechanical strength. The slopes failures have two models: plane failure and curve failure. In some of the strata, SO2-4 of groundwater that is strong corrosive is above 200mg/l. Slopes control countermeasures, such as drainage ditches, terrace drainage ditches, flooddischarge caves, discharge hole of elevation etc., should be properly designed on the basis of hydrogeology and engineering geology investigation to decrease water infiltration and dewater shallow ground water. 