Analysis of dynamic soil-pile response inmicropile group supporting loess landslide under earthquake action

The micro-pile has the advantages of fast and convenient construction and small disturbance, and has been used in the rapid treatment of loess landslide.In order to reveal the dynamic response law of loess landslide supported by micro pile, based on the dynamic visco-elasto-plastic constitutive model (VEP model), the seismic dynamic interaction mechanism between micropile and landslide is studied, and the reasonable pile spacing is discussed. The results show that the numerical calculation is close to the physical model test. The calculation results of VEP model after excitation are sensitive to the magnitude of earthquake. The model considers the visco-elastic-plasticity of soil and can reasonably reflect the displacement law of slope under earthquake. Under the action of the earthquake, the pile body of the micro-pile group produces bending shear failure, and the main failure position is located at 2~4 times the pile diameter above and below the sliding surface; it is suggested that the column spacing of micro pile group should be 5~7 times the pile diameter, and the row spacing should be 3~4 times the pile diameter.The research results can provide a basis for seismic design and numerical analysis of loess landslide prevention and control under earthquake.