降雨条件下松散堆积体滑坡破坏试验研究

Experimental Study on Landslide Failure of Loose Accumulation under Rainfall Condition

降雨是诱发松散堆积体滑坡的重要因素之一,研究降雨条件下松散堆积体滑坡的变形破坏与细颗粒迁移及入渗规律,对滑坡稳定性研究具有重要意义。本研究选取某松散堆积体滑坡土体为试验土样,采用人工降雨试验模拟松散堆积体滑坡的破坏。根据试验得到的土壤体积含水率、基质吸力数据,结合滑坡的破坏过程、降雨条件的定量变化,对堆积体滑坡的水—力条件进行分析,试验揭示了松散堆积体滑坡破坏过程是在非饱和状态下优先流与基质流共同作用的结果。通过定量分析对比滑坡破坏前后颗粒级配变化,证明了松散堆积体滑坡模式的不同会影响细颗粒迁移,且迁移量与降雨条件有关。

Rainfall is one of the important factors inducing landslide of loose accumulation body.It is of great significance to study the deformation and failure of loose accumulation body landslide and the migration and infiltration of fine particles under rainfall condition.In this study,the landslide soil of a loose accumulation body was selected as the test soil sample,and the artificial rainfall test was used to simulate the landslide failure of the loose accumulation body.Based on the data of soil volumetric moisture content and matric suction obtained in the experiment,combined with the failure process of landslide and the quantitative change of rainfall conditions,the water-force conditions of the landslide of the loose accumulation body were analyzed.The experiment revealed that the landslide failure process of the loose accumulation body was the result of the joint action of the preferential flow and the matric flow under the unsaturated condition.Through quantitative analysis and comparison of particle distribution changes before and after landslide failure,it is proved that the different landslide mode of loose accumulation will affect the migration of fine particles,and the migration amount is related to the rainfall condition.