Failure and post-failure kinematic disaster processes of columnar rock masses based on 3D discontinuous deformation analysis

Abstract

Columnar dangerous rock masses are considered important hazardous rock formations because of their ubiquity, abrupt failure, and high collapse frequency. The kinematic processes following their failure directly trigger geological disasters. This study investigates the failure and post-failure kinematic disaster processes of columnar rock masses using three-dimensional discontinuous deformation analysis (3D DDA). A comprehensive experimental system was established, and three sets of columnar laboratory models were employed to validate the 3D DDA simulations. Focusing on the Wangxia columnar rock mass, the failure and movement modes of single and multiple blocks were analyzed, considering the cutting of the structural planes within the rock column. Results demonstrated the high accuracy of 3D DDA in analyzing the kinematic disaster processes associated with the failure of columnar rock masses. With increasing number of cutting-surface combinations, the failure and movement modes of the blocks diversified and the durations of their oblique projectile motions after each collision with the slope decreased. Kinetic energy transfer between colliding blocks altered their initial trajectories and increased their movement durations compared with the observations for the single block. As the overall failure length of the columnar rock mass increased, the failure and movement modes of the blocks as well as the associated energy conversions changed, providing insights into the ensuing disaster mechanisms. Further, this study evaluated the impact of rock mass failure on highway traffic and predicted the disaster scope, providing a theoretical foundation for the development of disaster prevention strategies.