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| Physical modeling test on impacting fragmentation during landslide moving #br# |
| ZHOU Yue1，LIAO Haimei2，GAN Binrui1，CHENG Mingliang2，ZHOU Jiawen1#br# |
(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 The impacting fragmentation of high-speed rock landslides has a great influence on the motion characteristics，and the rapid dissipation of energy and the instantaneous change of the movement performance in the process of movement lead to an expansion of the affected area. Physical modeling tests were conducted with heaves to simulate multiple consecutive impacting between landslide mass and external uneven ground surface，and different quantities of unit test blocks with different material compositions and ratios were used in the tests to investigate the influence of the particle size and the volume of the block on the kinetic characteristics of the rock landslide movement. A high-frequency camera and digital cameras were used to record the whole motion process. The test results show that the overall time of the movement increased with the decreasing particle size and the increasing volume of the block. Moreover，the accumulation time was the controlling factor of the overall movement time. It is also shown that both the average velocity of the movement process and the velocity at the exit reduced with the decreasing particle size while changed insignificantly with the volume of the block/the number of unit blocks within 1 m/s. The energy dissipation caused by impacting fragmentation accounted for a small proportion of the total potential energy，but the impacting fragmentation was an important factor of energy dissipation during rock landslide movement and controlled the motion characteristics and energy dissipation mode of the landslide body.
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2020, Vol. 39 
