FIELD TEST AND NUMERICAL CALCULATION OF RESTITUTION COEFFICIENT OF ROCKFALL COLLISION
ZHANG Guangcheng1,2,XIANG Xin3,TANG Huiming1
(1. Faculty of Engineering,China University of Geosciences,Wuhan,Hubei 430074,China;
2. Three Gorges Research Center for Geo-hazard,Ministry of Education,China University of Geosciences,Wuhan,Hubei 430074,China;3. China Three Gorges Corporation,Yichang,Hubei 443002,China)
Abstract:For studying the characteristics and influence factors of restitution coefficient of rockfall collision,the field tests are carried out. By using the FASTCAM SA1.1 high-speed camera and the Motion Plus software,the velocities of rockfall before and after impact are obtained;and the normal restitution coefficient and tangential restitution coefficient are calculated. Meanwhile,the ANSYS/LS-DYNA software is adopted to simulate the test process;and the simulation results and test results are anastomotic well. The results show that:(1) While the ground material changes from fragment,accumulation layer to loose gravelly soil,the corresponding normal restitution coefficient decreases gradually;but the tangential restitution coefficient increases gradually. (2) The normal restitution coefficient is almost independent of the side length of rock block,incidence velocity and incidence angle;and it just affected by the physico-mechanical properties of ground material. (3) The tangential restitution coefficient is independent of the side length of rock block,but it increases with the incidence velocity and decreases with the incidence angle increase.