Phenomenon of Reduction in Friction at the Toe of Gravity Landslide under Seismic Vibration Effect
G. G. Kocharyan1, Z. Z. Sharafiev1, S. B. Kishkina1, Qi Chengzhi2
1Academician Sadovsky Institute of Geosphere Dynamics, Russian Academy of Sciences, Moscow, Russia 2Beijin University of Civil Engineering and Architecture, Beijin, China
Keywords: Slope-related phenomena, landslides, strain accumulation, creep, seismic vibration, earthquakes, blasts
Abstract
The article describes the lab-scale testing of dynamic instability in a block placed on a rough slope surface and subjected to small-amplitude vibrations. It is shown that the macroscopic sliding evolution is well-presented using equations of creep with the properly selected constants. According to the testing data, the necessary condition of the dynamic failure is the critical displacement along the slope and the certain creep rate. The critical displacement appears to exceed greatly the typical value when the sliding surface transits to the residual shear resistance. It is found that the landslide body instability develops at the late stage due to the phenomenon of reduction in friction at increasing sliding velocity.
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