Study on the Deformation Mechanism of the Wangxia Unstable Rock Mass in the Three Gorges Reservoir

Abstract

Twice serious deformation occurred in the Wangxia unstable rock mass in 2010 and 2011 in Wushan country in the Three Gorges Reservoir. It formed a large dangerous factor for the local resident and channel safety. Based on the detailed investigation of the new cracks, deformation history, GPS observations, total station monitoring and crack displacement monitoring data analysis, analyzed comprehensively the deformation and reasons of the unstable rock. The researches show that the deformation type of the unstable rock mass contains gradual change and mutation, should adopt the corresponding monitoring methods and monitoring frequency in different deformation stages based on the geological survey and monitoring the key parts of the unstable rock mass. The destruction of the Wangxia unstable rock was a gradual process, controlled by 5 key cracks, which were crack T11, T12, T13, T16, and T10, consider the Wangxia unstable rock was subsided extrusion type collapse.