降雨入渗下炭质页岩路堑边坡渗流特性研究

摘要

The cutting slope model of carbonaceous shale is established with Seep software Geo-studio to study the variation law between pore water pressure and volume water content in the slope within the duration of rainfall.The results show that the under larger rainfall intensity,the rainwater infiltrates into the rock fleetly,leading fast increase of pore water pressure,however,most rainfall will flow away along the slope.Under long time of rainfall,the rainwater will infiltrate downward along the fracture of the rock,causing large impact on the pore water pressure of the deep rock gradualy.Under short time of rainfall,a transient saturation region may be formed on the surface of the slope,however,with the long time of rainfall,lots of rainwater will infiltrate into the slope,leading constant increase of underground water level and a saturation region will be formed in a large scope of the slope toe and extend to the top of slope.After the rainfall,the transient saturation region will be disappeared slowly and the water content of the rock decreased gradually,however,dissipated slowly due to long duration of rainfall.%运用Geo-studio软件建立炭质页岩路堑边坡模型,对降雨历时内边坡中孔隙水压力和体积含水率的变化规律进行了研究.结果表明:降雨强度较大,雨水会快速入渗岩体,使孔隙水压力增加较快,但大部分雨水会沿边坡流走;降雨时间长,雨水会逐渐沿岩体裂隙向下入渗,对较深处岩体孔隙水压力产生较大影响.降雨在短时间内,边坡表面会形成暂态饱和区,随降雨时间的延长,大量雨水将入渗到坡体内,使地下水位不断上升,在坡脚处较大范围形成一个饱和区域,并向坡顶方向延伸.降雨结束后,暂态饱和区慢慢消失,岩体含水率也逐渐降低,但降雨持续时间长,岩体含水率消散的速度较慢.