| The research and application of static stability analysis for slopes at home and abroad are very extensive.However,the research on slope stability is confined to the influence of seismic vibration on slopes.Besides,the research on the dynamic response and stability of the slope under the action of dynamic pile driving load hasn’t been mature yet.In the present paper,the combination of indoor physical simulation test,dynamic triaxial test,theoretical analysis and engineering application are adopted to investigate the stability of the clay soil slope under dynamic pile vibration.The main work and conclusions are as follows:(1)The dynamic response model test of the cohesive soil slope under pile driving was designed and completed,and the issues on boundary condition processing were discussed.Based on the measured experimental data,the dynamic characteristics and dynamic response law of the cohesive soil slope under the influence of factors such as the shape of the slope,the slope ratio and the distance between the pile driving point and the slope foot were studied.(2)Taking a saturated cohesive soil in a pit in Yangzhou as the research object,a consolidation and undrained test was performed by a DDS-70 microcomputer-controlled electromagnetic vibratory triaxial apparatus.The dynamic shear strength and dynamic shear stress ratios of soil under different consolidation stress ratios and confining pressures were studied,and the correlation curves between ratios and the failure times were obtained.Destruction envelope was made according to the relationship between the Kf envelope and the intensity envelope.Thus the dynamic strength parameters of the soil samples were obtained.(3)The researcher analyzed the law of the generation and attenuation of pile vibration acceleration and its influence on slope stability by employing the pseudo-static method to equate vibration acceleration as vibration inertial force in slope soil.Finally,through the analysis of the force of slope soil,the calculation formula of slope stability safety factor under the action of pile vibration was deduced.(4)In combination with a foundation pit project in Yangzhou,the main reasons for the collapse of the slope were analyzed.The calculation formula for the slope safety factor under the effect of dynamic pile driving was derived.Compared with the calculation formula of the Swedish segment method,the former calculation result is in line with the actual project. |
