Shaking Table Test On Dynamic Response Of Compacted Slope

The dynamic response of slope under seismic load has always been a hot topic in the field of seismic engineering.China is the world's most concentrated continental earthquake,one of the highest activity in the history of China's earthquake number is not a few.Earthquake is an important factor that induces landslide.In recent years,with the increase of large-scale engineering construction in China,landslide accidents are increasing.As one of the landslides,accumulation layer landslide is facing a severe test in western China,which is dominated by accumulation overburden layer.At present,the research on the seismic design of slope is not very perfect,which also seriously affects the seismic design and construction of slope.Therefore,the in-depth study of the dynamic response of slope under seismic load has important theoretical and practical significance for the construction and design of geology and geotechnical engineering.In this paper,after the investigation and analysis of the landslide site,the simplified prototype of the landslide has completed the shaking table model test,and combined with the numerical simulation method,the dynamic response law and failure mechanism of the slope under the earthquake action have been studied and discussed.The following results have been achieved:1.Through the field investigation,combined with some typical characteristics of landslides and geological disasters,the influence of topography and landform,cultural and geological conditions,human influence and weathering on slope stability in this region is analyzed.2.After a full understanding of previous studies on similar materials and based on the similarity theorem,the configuration of similar materials with iron powder + barite powder as aggregate is completed to meet the material requirements of model test.3.Select the locust deposit slope of village as the research object,through the shaking table model test of the main research aspects:(1)to study the dynamic characteristics of the slope model,analysis model in the sine wave,the acceleration response of the EI,wolong seismic wave,found that due to the slope foot are inhibitory effect of acceleration amplification factor lead to slope foot acceleration amplification factor significantly less than the acceleration amplification coefficient of mesa.Under the same seismic wave loading,the acceleration amplification coefficient will increase with the increase of slope height,showing the elevation amplification effect.At the monitoring points in the horizontal direction,the acceleration amplification coefficient also increases along the slope from the inside to the outside,showing a surface effect.(2)The dynamic response law and failure mechanism of the model under the loading of seismic waves with different waveforms,frequencies and amplitudes are analyzed.(3)The failure process of the model was analyzed through the scanner and video revisit.The overall performance of the model was earthquake induced-leading edge shearing-traction slide-accumulation of slope toe.In terms of the failure mechanism,the front part was destroyed first and then the middle part was destroyed by traction failure.4.The following analyses were carried out through numerical simulation :(1)The simulation test results were compared with the model test results for verification.(2)The influence of frequency and amplitude of seismic wave on the dynamic response of the model is analyzed.It is found that the frequency of seismic wave has obvious influence on the model.To a certain extent,with the increase of seismic wave frequency,the acceleration amplification coefficient of the model also increases.However,the amplitude variation of seismic wave has no obvious effect on the dynamic response of the model.In the simulation test,the elevation amplification effect and the surface effect in the model test are also shown.