黏土砾石层边坡原位冲刷试验研究

Experimental Study on in Situ Scouring of Slopes of Clay Gravel Layer

安庆组黏土砾石层是由砾卵石和黏土组成的一种特殊地质体,其胶结力会受水的影响而大幅降低,引发一系列工程地质灾害,有必要在现场开展边坡降雨冲刷试验,研究不同坡度的边坡在降雨过程中的破坏形态及失稳机理。结果表明:黏土砾石层边坡在降雨冲刷过程中,坡面冲沟的形成大致分为以下三个阶段:表面侵蚀阶段、细沟形成阶段和冲沟网络的形成阶段。边坡的坡度越大,越有利于坡面冲沟的形成和扩展,不利于边坡的稳定;黏土砾石边坡坡面砾石是否滑落主要取决于边坡坡比。研究成果可为当地边坡的防护和治理提供参考。

The clayey gravel layer of the Anqing Formation is a special geological body composed of gravelly pebbles and clay. Its cementation force will be greatly reduced by the influence of rainfall, causing slope instability and damaging surrounding farmland and public facilities. Therefore, in this paper, the slope rainfall erosion experiment was carried out at the site to study the failure pattern and instability mechanism of slopes with different slope angles in the process of rainfall. The results show that the formation of slope ditches in the process of rain erosion of clayey gravel layer is roughly divided into the following three stages: surface erosion stage, fine trench formation stage and gullage network formation stage. At the same time, the larger the slope of the slope, the more conducive it is to the formation and widening of the slope ditch, which is not conducive to the stability of the slope. At the same time, whether the gravel on the slope of clayey gravel rolls down depends mainly on the slope ratio. The research results can provide a reference for the protection and treatment of local slopes.