Study On Features And Cause Mechanism Of Debris-Bedrock Interface Landslide

As geological condition and structure complex in China, the country has suffered from serious geological hazards. And the landslides are the main kind of geological disasters, which restrict the development of national economy and threaten property safety. The debrisbedrock interface landslides are widely distributed in the southwest and northwest area of China, but the genetic mechanism and formation mechanism are not revealed thoroughly in the existing researches.Collecting the debris-bedrock interface landslides instances and analyzing the potential geological disasters detailed investigation in Langao County, Ankang City, summarized the features of debris-bedrock interface landslides. Then the paper discussed the laboratory tests results of soil-rock mixture materials and rock-soil interface physical and mechanical properties. Finally, revealed the genetic mechanism and formation mechanism of Zushimiao Landslide in Langao County, by numerical simulations. And the conclusions are as follows:(1) Collecting the debris-bedrock interface landslides instances and analyzing the potential geological disasters detailed investigation in Langao County, summarized the geological environment features, structure characteristics and basic dynamic characteristics.(2) According to the laboratory tests results, the soil-bedrock interface is the weak structural plane which leads to the debris-bedrock interface landslide by comparison the strength between soil-rock mixture materials and soil-rock interface.(3) By the numerical analysis result of displacement, stress and maximum shear stain in both natural state and the seepage state. Conclusions are as follows:(a) the soil- bedrock interface as weak structural plane is control factor;(b) the surface water infiltrating and groundwater seeping are triggering factors. The debris-bedrock interface landslides occurred by combination of the two factors.