Study On Calculation Method For Lateral Earth Pressure On Parallel Retaining Walls Considering Soil Arching Effect

The determination of forces on structures which are connected to earth mass is ofparamount importance in applied geotechnical engineering. Soil arching effect and thecomputation of the related earth pressure had been hot topics in geotechnical engineeringfor many years. In this dissertation, on the basis of the studies so far available, soilarching effect and earth pressure for parallel retaining structure are studied in-depth.With soil arching effect considered, circular arch form as the trajectory of minorprincipal stress and parallel retaining wall filled with clayey soil as object, both thecoefficient and formula of lateral earth pressure on parallel retaining wall were derivedwith mechanical unit equilibrium equation and Mohr-Coulomb strength theory,with theeffect of soil-wall friction angle,internal friction angle, cohesion of backfill,verticaluniform load and horizontal distance between parallel walls considered. The influencelaws of the soil-wall friction angles with full and part effect and the horizontal distancebetween parallel walls on the lateral earth pressure were obtained through examplesanalysis. The results show that the coefficient of lateral earth pressure and lateral earthpressure itself are in nonlinear distribution along the depth with soil arching effectconsidered,and are related with soil-wall friction angle,internal friction angle ofbackfill,cohesion of backfill, vertical uniform load and the horizontal distance betweenparallel walls. The conventional method for earth pressure without consideration of soilarching effect is not safe.By conducting the model test of parallel retaining wall to the earth pressure, itshowed that the parallel retaining wall lateral earth pressure was nonlinear. Compared withthe theoretical value, theory on caculation of retaining wall backfill parallel lateral earthpressure as the effect of soil arching was considered, was proved to be practical.Parallel retaining wall was analyzed by ABAQUS finite element software to conductsome numerical simulation, which helped to reveal the influnce of retaining wall’s activeearth pressure caused by the rate of hight and width, the soil-wall friction angles andcohesion, and varying pattern of lateral earth pressure in varying subsidence displacement, following by the achivement of retaining wall’s slip shifting surface.