非饱和土边坡降雨入渗过程及最大入渗深度研究

Study on Rainfall Infiltration Process and the Biggest Infiltration Depth for Unsaturated Soil Slope

系统分析了降雨入渗对土体基质吸力、土体应力、位移的影响,并对非饱和土边坡降雨入渗过程进行了总结分析,首次从能量角度提出了降雨入渗最大深度的概念,认为雨水能够在土体中下渗,主要是因为存在一定的驱动势能差,通过推导,得出了最大入渗深度的计算公式,该公式与土体的孔隙水压力有关。由于降雨而引起的边坡土体滑坡中,绝大多数滑动面都在边坡土体的最大入渗深度的范围之内,通过对最大入渗深度和滑动面的关系研究,可以初步估计滑坡规模,从而在滑坡治理中计算确定滑动面,合理地确定治理方案的参数,如锚杆或土钉的长度、抗滑桩的长度等。

The influence of the rainfall infiltration on the matric suction, soil stress and displacement of soil is analyzed systematically for unsaturated soil slope. The rainfall infiltration process is summarized and analyzed. And based on the energy equilibrium, the biggest infiltration depth is put forward for the first time. Research shows that there will be rainfall infiltration for the soil due to the existence of difference in driving potential energy. The equation for calculating the biggest infiltration depth is deduced by the theoretical analysis, which links to the pore water pressure. As for the rainfall-induced landslide harzards, most of the sliding occurrence is within the range of the biggest infiltration depth. By studying the relationship between the biggest infiltration depth and sliding surface, the landslide volume can be primarily estimated, so the sliding surface can be confirmed, which is important for determining those parameters in the treatment program, such as the length of anchor, soil nail and anti-slide pile.