Dynamic Response Of Rock Slope Under The Action Of Seismic Force And Reservoir Water Using Shaking Table Tests

As a green energy resource,hydraulic resources have been paid more and more attention by more and more countries.The total amount of water resources in China is rich,but the distribution is uneven.The western regions such as Sichuan,Yunnan,Tibet have concentrated about 70% of our country's hydraulic resources.After the Wenchuan earthquake,the landslides occurred frequently in the western region,it is very important to study the stability of the slope under the combined action of earthquake and reservoir water.In this paper,taking the Xiang Li high-speed bridge slope of Jinsha River as the research object,using the method of finite element analysis,analysis of the slope acceleration response and strain response of rock slope was considered.A large-scale shaking table model test for rock slope considering the change of reservoir water level is carried out.The dynamic response characteristics and failure mechanism of the slope model are studied,especially the influence of the sudden drop of reservoir water on the slope stability.Considering the factors of reservoir water level,the distribution of weak structural planes and the landform features of the bridge site of Jinsha River,the two-dimensional finite element model of slope is established,and the dynamic response characteristics of the slope under the action of seismic force are analyzed.The input waveform of the ground motion is different intensity artificial synthetic wave,and the hydrostatic pressure is applied to the calculation model to simulate the effect of the reservoir water.The calculation results show that the acceleration response is enlarged along the slope height and the direction of the slope,and the maximum value appears at the anchorage of the surface of the slope.Under the condition of the same seismic load,when the water level is directly affected by the reservoir water,the acceleration peak value increases obviously after the water level drops,so the sudden drop of reservoir water is not conducive to the dynamic stability of the slope.A large-scale shaking table model test for rock slope with weak structural plane is designed and carried out.The dynamic response rule and failure mechanism of rock slope under combined action of reservoir and earthquake force are studied.By injecting water and pumping water into the model box to simulate the rise and fall of the reservoir water level,the wave reflecting wave caused by the tank wall caused by the box wall is weakened by using the wave elimination device.The fracture observation of the model under the combined action of reservoir water and seismic force shows that reservoir water infiltration aggravates the crack expansion of the slope.The results of acceleration response show that the sudden drop of reservoir water makes the acceleration amplification effect of the slope surface more obvious,which is not conducive to the stability of the slope.The failure mode of the slope is that,crack in slope caused by earthquake along the dip structural plane crack,seismic load increase and water infiltration increased crack propagation,along dip structural plane through cracks;in seismic forces,water infiltration and water drop under the combined effect of the slope along the inclined structural surface overturning and sliding failure.