关键词: 降雨入渗; 堆积体; 裂隙发育; 模型试验; 湿润锋;

Abstract: Cracks in deposit have important influences on rainfall infiltration.Influences of two types of cracks,Y-type cracks and the primary-secondary combined feather-like cracks,on rainfall infiltration of landslide deposits were studied by physical simulation experiment.Through analysis on the change characteristics of pore water pressure,volumetric water content and matrix suction of deposits with both types of cracks,the following findings could be obtained:(1)the raindrops infiltrated into the deposits with two types of cracks were in generally similar way,which can be summarized as 3 stages:surface wetting,strong immersion and diffusion at the cracks,horizontal and lateral wetting;(2)in Phase II,rainfall infiltration mechanisms of the two types of cracks varied greatly,namely the diffusion effect of feather-like crack was stronger than immersion effect,while the Y-shaped crack had a contrary phenomenon.(3)Raindrops were easy to immerse deep into the deposit through feather-like cracks,showing greater impact on the stability of the deposit than Y-shaped cracks.

Key words: rainfall infiltration; deposit; crack development; model test; wetting front;