Research On Mechanical Behavior Of Counterbalanced Retaining Wall Based On Discrete Element Method

The stability of backfill and retaining structures is an important topic of geotechnical engineering.This paper takes the roadbed widening and reconstruction of the counterweight shoulder retaining wall in Ganzi Prefecture of the 318 National Highway from Erlang Mountain to Kangding as the project prototype.),rotation around the toe of the wall(RB)and rotation around the top of the wall(RT)three active displacement modes,the virtual test model of the counterweight retaining wall was established by the discrete element method,and a more comprehensive study was carried out from the mesoscopic level.Mechanical behavior characteristics of retaining walls and fill during limit state.The main research contents are as follows:Firstly,based on the classical earth pressure theory,the earth pressure calculation methods of retaining walls(polygonal wall back,second rupture surface,vehicle load,etc.)and counterweight retaining walls and lower walls under special circumstances are described and summarized.,the earth pressure of the counterweight retaining wall design model based on the roadbed widening and reconstruction project is calculated by the theoretical calculation method.Secondly,the significance,principle and error analysis of the geotechnical centrifugal model test are briefly described,and then three different active displacement modes(T,RB,RT)centrifugal model tests that also rely on the roadbed widening and reconstruction project are selected.The earth pressure distribution and rupture surface morphology of the retaining wall in the non-limit state process are described respectively,which provides a comparative reference for the numerical model test.Finally,based on the roadbed widening and reconstruction of the balance-weight road shoulder retaining wall project in Ganzi Prefecture in the Erlangshan-Kangding section of National Highway 318,the centrifugal model test under three active displacement modes of the balance-weight retaining wall is used as a physical reference,and the discrete element method is used to separate the The virtual model test of three active displacement modes(T,RB,RT)of the retaining wall was carried out.The soil pressure distribution at the back of the wall,the displacement of the backfill,the shape of the cracked surface of the fill and the distribution of the particle contact force chain were analyzed from multiple angles.The mechanical behavior of retaining wall and soil filling in the non-limit process is analyzed comprehensively at the mesoscopic level.The purpose of this paper is to study the distribution of the non-limit active earth pressure and the displacement of the backfill of the counterweight retaining wall under different displacement modes,and to provide a certain reference for the related subgrade supporting projects in this area in the future.