Study on failure precursors and seismogenic mechanisms of a large landslide based on moment tensor analysis
LI Shulin1，LIN Kaifan1，ZHOU Mengjing1，ZHANG Jianlin1，HONG Yong1，HU Jingyun2，PENG Fuhua2
(1. School of Architecture and Civil Engineering，Xiamen University，Xiamen，Fujian 361005，China；2. Changsha Institute of Mining Research Co. Ltd.，Changsha，Hunan 410012，China)
Abstract：The seismogenic mechanisms of engineering rock mass are the basis for both research and application of monitoring and early warning of rock failure. In this paper，based on the locating data of the precursory microseismic sources from a project case of a large-scale failure of the overlying rock mass over the mining goaf induced by a large blast，a back analysis of the seismogenic mechanisms was carried out by applying the moment tensor method to the precursory microseismic location events，and the pure double-couple components were obtained by calculating and decomposing the moment tensor of the monitored microseismic localization events. The value of the discriminant parameter R，was calculated by the Feigner and Young moment tensor fracture criterion and used to determine failure types of the rock mass with the precursory microseismic events. The volume parameters of unchangeable part T and changeable part k were calculated according to the moment tensor components，and the T-k chart of Hudson source type was plotted. It is shown that the main failure type of the precursory sources is shear failure. Furthermore，the fault parameters of the locating sources were calculated according to the pure double-couple components . The shear failure type of the precursory microseismic events analyzed by the focal mechanism solution basically matches with that of the on-site macroscopic shear-slip failure of the large landslide over the mining goaf. The research results show that the precursory focal mechanism solution based on microseismic moment tensor theory can more accurately determine the failure type of meso-scale engineering rock mass. The results of this study can be the reference to further research on the failure mechanisms of rock mass as well as early warning of engineering rock mass disasters.
李庶林1，林恺帆1，周梦婧1，张建霖1，洪 勇1，胡静云2，彭府华2. 基于矩张量分析的特大山体破坏前兆孕震机制研究[J]. 岩石力学与工程学报, 2019, 38(10): 2000-2009.
LI Shulin1，LIN Kaifan1，ZHOU Mengjing1，ZHANG Jianlin1，HONG Yong1，HU Jingyun2，PENG Fuhua2. Study on failure precursors and seismogenic mechanisms of a large landslide based on moment tensor analysis. , 2019, 38(10): 2000-2009.
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2019, Vol. 38 
