Rockfall Hazard Assessment on Wangxia Rock Mass in Wushan (Chongqing, China)

Wangxia rock mass was situated in Three Gorges around Yangtze River and considered to be one of largest unstable rock mass in China. The present study aims to investigate the damage of Wangxia rock mass and protect the lives of people and shipping from rockfall phenomenon. Mohr–Coulomb model in Universal Distinct Element Code was built to find out the rockfall initiation position. RocFall 4.0 program has been used to calculate horizontal location of rock end-points, maximum bounce heights, total kinetic energy, and translational velocities of the falling blocks of different weights and the input parameters were obtained by back analysis. The results show that the maximum value of bounce height and total kinetic energy is 3.63 m and 2819 kJ respectively at the horizontal location of 152.4 m, where proper protection measures should be adopted to minimize the risk of the damage of the Wangxia rock mass. Finally, the results of simulation indicate that a barrier of 5 m height and 3000 kJ absorption capacity is enough to resist the falling stones.