Study On Earth Pressure Of Rigid Retaining Wall With EPS Cushion Behind The Wall

Retaining wall,as an important retaining structure,is widely used in civil engineering.Setting an EPS cushion behind the rigid retaining wall can increase the actual lateral displacement of the backfill and effectively reduce the earth pressure acting on the wall.However,the current studies on the decompression effect of EPS cushion are limited to the case that the retaining wall does not move and the backfill meets the assumption of semi-infinite.Aiming at the deficiencies of the existing researches,the study on the earth pressure of rigid retaining wall with EPS cushion behind the wall with different backfill widths is carried out through model test and numerical simulation.The main research contents and conclusions are as follows.(1)The self-made model box is used to carry out the model test on the retaining wall with/without EPS cushion behind the wall with different backfill widths,and the decompression efficiency of the EPS cushion is defined to quantitatively analyze the decompression performance of the EPS cushion behind the retaining wall.The results show that the increasing trend of the static decompression efficiency gradually accelerates with the decrease of the elastic modulus of the EPS cushion,and gradually slows down with the increase of the thickness of the EPS cushion.(2)The finite element model of the retaining wall with actual size in engineering practice is established by using the finite element software ABAQUS,and the horizontal movement situation of the rigid retaining wall with EPS cushion behind the wall is simulated.The distribution law of static earth pressure,active earth pressure and EPS cushion compression of the retaining wall with EPS cushion behind the wall is studied.And the variation law of the active decompression efficiency and horizontal compression of the EPS cushion with the parameters of the EPS cushion and the ratio of width to height of the backfill is further analyzed.The results show that the static decompression efficiency first increases and then decreases with the increase of the ratio of backfill width to height,and the active decompression efficiency increases with the increase of the ratio of backfill width to height;the larger the ratio of backfill width to height,the smaller the elastic modulus of EPS cushion and the larger the thickness of EPS cushion,the greater the horizontal compression of EPS cushion.(3)According to the analysis results,the reference range for the density and thickness of the EPS cushion in the actual retaining wall engineering is proposed:the EPS cushion material in the density range of 16 kg/m~3?20 kg/m~3 and close to 0.04 times the wall height thickness range is selected to ensure that the retaining wall can achieve high decompression efficiency when it is static or displacement occurs.