Analysis Of Failure Mechanism And Stability Of Slope Under Earthquake

China is a seismic active country. In recent decades, many violent earthquakes had happened. It is also a mountainous country with many natural and artificial slopes. Under the power of great earthquakes, these slopes may lost their stability which could cost heavy casualties and property loss. Studies on slope have been focused on the response characteristics and stability analysis of the slope under static loading and very little research work has been done on the slope stability under earthquake. Thus, the stability analysis of slope plays an indispensable role on both academic value and economic benefits.The main research work and conclusions in this paper are as follows:1. Adopt different geotechnical yield criterion for a domestic slope stability analysis, and concluded the corresponding safety factors, then compared with the calculation results of the traditional limit equilibrium method. Results show that the safety factor calculated by DPI yield criterion is larger. Under the plane strain condition, the safety factor calculated by DP4 yield criterion matching with Mohr-coulomb criterion is more reasonable.2. Effects of cohesive force, friction angle, elastic modulus and tensile strength on stability of the slope were researched. The results showed that:(1) with the increase of cohesive force, the greater the safety factor of the slope; the slope sliding is changed from the shallow sliding to the deep sliding. (2) with the friction angle increases, the greater the safety factor of the slope; the slope sliding is changed from the deep sliding to shallow sliding, and the relationship between the cohesive force and the sliding surface is just the opposite. (3) with the increase of the elastic modulus, the safety factor of the slope with no supporting structure is basically unchanged, and for different elastic modulus, the positions of the sliding face are substantially coincident. (4) Within a certain range, with the increase of tensile strength, the greater the slope safety factor. But its influence on the safety factor is obviously smaller than the friction angle and cohesive force.3. In the analysis of the stability of the slope under earthquake, the failure mechanism of the slope should be made clear. Based on the strength reduction method, the failure mechanism of slope under earthquake is analyzed numerically. The study shows that the failure of slope under earthquake is made up of the tension failure in the upper part and the shear failure in the lower part instead of shear sliding failure.4. The safety factor based on tension-shear failure mechanism is smaller than the safety factor based on tension-shear mechanism under earthquake, it mainly because of the effect of the tensile damage, and it tends to be safe.