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| Physical modeling test for entrainment effect of landslides and the related mechanism discussion |
| LU Pengyuan1，HOU Tianxing2，YANG Xingguo1，HAO Minghui2，ZHOU Jiawen1 |
(1. State Key Laboratory of Hydraulics and Mountain River Engineering，Sichuan University，Chengdu，Sichuan 610065，China；
2. College of Water Resource and Hydropower，Sichuan University，Chengdu，Sichuan 610065，China) |
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Abstract During the high-speed movement of landslide-debris avalanches，the effect of erosion on the substrate material increases greatly the sliding volume and expands the disastrous zone. The effect of the particle size and volume of slide materials and the effect of the particle size and the thickness of substrate materials on entrainment process were studied with the physical model tests. A high frequency camera of the type of MotionPro-Y3–S1 was used to observe the process of substrate entrainment. The test results revealed that the sliding materials of high-speed movement impacted and eroded the substrate strongly and make the substrate splash with great velocity and move forward after being sheared. The entrainment distance increased with the growth of volume and grain size of slide materials as well as the particle size of the substrate materials while decreased with the growth of erodible substrate thickness. The impact failure was shown at the front of the debris avalanches，which damaged the substrate and brought entrainment due to impacting force. The shear movement at the middle and rear part caused the shear failure of substrate materials due to the shearing force.
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2016, Vol. 35 
