Research On Seismic Response And Dynamical Stability Of Slope

Earthquakes occur frequently in our country, which is very mountainous. The slope failure induced by earthquake,such as collapse\debris flow\landslide,is the common form in the hilly area. Recently sliding mechanism,which study on the slope failure on is made from, is analyzed qualitatively. Some aspects,simulation and theoretic calculation, need to been carried out in depth for evaluating Seismic Response and Dynamical Stability of slope. So there is important academic significance and application value for a high-incidence and high-intensity earthquake area to analyze of seismic dynamical response feature.Typical landslide in the yushu airport highway of qinghai province is used as the prototype of simulation in this thesis. Based on finite difference software-FLAC3D and time-domain analysis, the dynamical response feature of acceleration in different parameters(PGA\duration\spectrum feature\the cohesion\elastic modulus) is calculated. To calculate the numerical value of acceleration amplification factor, the fitted formula about distributions of acceleration amplification factor is obtained.The pseudo-static method is modified via this formula. That acceleration is accentuated with height of slope, as a non-liner dynamical feature,is taken into account. In this way, safety factor is calculated and the stability of slope is evaluating. The dynamical response feature under the joint actions of horizontal and vertical accelerator is researched, that establish good base for more analyzing of stability. The main achievements are as follows:1Under horizontal earthquake wave, there is vertical and horizontal amplificatory effect to the input seismic waves from slope. The earthquake peak values gradually increases with accretion of height, which can reach maximum in the top of slope. At the same height, magnification coefficient of accelerator increases from internal slope to shallow slope, while there is outstanding surface amplificatory effect at shallow slope. Variation of acceleration amplification factor with height is fitted.2Based on dynamical response of acceleration, the pseudo-static method is improved with considering non-liner amplificatory effect of acceleration. The stability factor is calculated by fitting formula. It can be obtained by example that the stability factor calculated by the modified pseudo-static method is smaller than the traditional pseudo-static method, which can show that the modified pseudo-static method is more actual.3Under the joint actions of horizontal and vertical earthquake wave, there is vertical and surface amplificatory effect to the input seismic waves from slope. The earthquake peak values gradually increases with accretion of height, amplification effect of bottom slope is not evident with slow increase, and relatively significant amplification effect exists in top slope. At the same height, magnification coefficient of accelerator increases from internal slope to shallow slope with the max value at shallow slope. From the distribution rule of magnification coefficient, it is known that horizontal amplification effect of earthquake accelerator is more significant than vertical one under the joint actions of horizontal and vertical accelerator.