Study On Seismic Response And Vulnerability Of Slope In Fushun West Open-pit Mine

The slope structure of the Fushun West Open-pit Mine is complex,and the inclined slope in the Nanbang is affected by weak layers,and it is easy to induce landslide disasters under the action of earthquakes.In order to study the dynamic response and vulnerability change law of the inclined slope with weak layer in Nanbang under the action of earthquake,the method of combining theoretical analysis and numerical simulation is used to study the dynamic response and vulnerability of the slope,using the finite difference software FLAC^3Dconducts nonlinear time history analysis of the slope,obtains the dynamic response variation law of different positions and different rock layers of the slope,and changes the dynamic load amplitude to study the influence of the ground motion intensity on the dynamic response of the slope;the Newmark slider method is used to calculate the compliance of the slope.Analytical solution of dynamic response of inclined layered slope using Newmark slider method,determine the vulnerability index（DM）based on the dynamic response law of the slope and the IDA method,establish the functional relationship between the vulnerability index and the ground motion intensity index,and combine the dynamic response and limit state of the slope The failure probability of the slope is obtained,and the failure probability reflects the vulnerability of the slope.The main findings and conclusions of the paper are as follows:（1）The nonlinear dynamic analysis method is used to study the variation law of the seismic response of the inclined slope with weak layer.The research results show that there is an elevation amplification effect of the weak layer and the rock mass on both sides of the weak layer,and there is a significant difference in the displacement on both sides of the weak layer.The ground motion decays through the weak layer,the kinetic energy decreases,and the deformation energy increases,and the weak layer is the plastic deformation region of the critical state of the slope.（2）Comparing the analysis results of the seismic response of the slope under one-way and two-way earthquakes,the newly added vertical ground motion component will increase the vertical acceleration,velocity and displacement amplitudes of the slope,while the horizontal acceleration,velocity,displacement amplitudes and frequencies are basically unchanged.The amplitude and frequency are basically unchanged,and the dynamic response of the slope in the horizontal direction is much larger than that in the vertical direction.（3）On the basis of the seismic response analysis of the slope,the vulnerability index is obtained by calculating the velocity of the weak layer and both sides of the weak layer.The vulnerability index is affected by the backfill body of the slope,the intensity and type of ground motion,and the vulnerability index can reflect the characteristics of slope and ground motion uncertainty.（4）The vulnerability of slopes at different positions is studied,and the failure probability of E200,E800,and E1000 section slopes is calculated by using the vulnerability model.When the slope is completely damaged,the corresponding failure probability is E800 section slope>E200section slope>E1000 section slope,E800 section slope has high vulnerability,and E1000section slope has relatively low vulnerability.（5）The failure probability of the section slope at the same position under the action of the two-way earthquake is greater than that under the action of the one-way earthquake,and the results are consistent with the actual situation.Comparing the failure probability matrix,the damage grades of the slope under the action of one-way and two-way earthquakes are obtained.The damage grade reflects the vulnerability degree of the slope,and there are differences in the damage grade of the slope at different positions,which is consistent with the failure probability analysis results.The paper has 111 figures,15 tables,and 80 references.