Research On The Damage Law Of The Layered Unstable Rock Community Collapse Induced By Earthquake

The thesis give quantitative analysis of factors on the community collapse of layered unstable rocks through discrete element numerical simulation and get different failure modes and failure characteristics and summarize the laws of community destruction as well as the precursor feature of collapse and make the following main conclusions:1. Summarize the influence factors of the community collapse of layered unstable rocks as three main factors of geological, terrain and seismic wave conditions, refine them into 7 different conditions, that is : occurrence height of the dangerous rocks, height of of the dangerous rocks, slope of stiff cliff, thickness of the dangerous rocks, degree of fragmentation, dip angle of levels and amplitude of earthquake. Set up the numerical model of the cliff layered unstable rock community through UDEC discrete element software under different parameter conditions and let it crumble under the simulation seismic waves, record the collapse process and the trajectory of avalanche block and lateral and vertical displacements, study the failure modes and failure laws of the layered unstable rock community under different geological, terrain and seismic wave conditions.2. Based on research one, summarize and analyze the collapse point based on time of the cliff layered unstable rocks and put forward the concept of “displacement angle” based on the vertical and horizontal displacements of avalanche block to get precursory features of collapse in different situations.3. Introduce the Analytic Hierarchy Process to systematically and quantitatively study the influence degree of different geological, terrain and seismic wave conditions on the collapse of layered unstable rocks, choose the single level model structure and regard the 7 main factors of occurrence height of the dangerous rocks, height of of the dangerous rocks, slope of stiff cliff, thickness of the dangerous rocks, degree of fragmentation, dip angle of levels and amplitude of earthquake as evaluation factors,do expert scoring of the relative importance of different factors based on the summary of relative reference and results of numerical simulation above and finally get theinfluence degree of different factors based on the linear algebra knowledge which can provide foundation for risk assessment of collapse of regional geological disasters in broken and unstable rock regions.