STUDY OF ACTIVE EARTH PRESSURE ON RETAINING WALL SUBJECT TO TRANSLATION MODE CONSIDERING LATERAL PRESSURE ON ADJACENT EXISTING BASEMENT EXTERIOR WALL

In the case of retaining wall adjacent to existing basement and the backfill?s width is limited,it is not strict to use classical Coulomb or Rankine theory to calculate the active earth pressure.The results obtained from finite element method(FEM) show that when the retaining wall translates and the backfill is under fully active limiting state,the sliding soil wedge does not break away from the adjacent basement exterior wall;the lateral pressure from the basement exterior wall cannot be neglected.It also shows that multiple slip surfaces occur in the backfill if the backfill?s width is very small.The earth pressure above the intersection point between the last slip surface and the retaining wall or the adjacent basement exterior wall is approximately equal to the Coulomb active earth pressure.Based on the numerical results,a new theory model to calculate the earth pressure for limited soils is presented.The solving method for calculating the active earth pressure coefficient and the first slip surface inclination are provided.Using the horizontal differential element method,the theoretical formulae of the distribution of active earth pressures on retaining wall and the relative height of the application point of the resultant earth pressure are obtained.Comparisons of the calculated results with solutions obtained from the proposed method,the classical earth pressure theories,the other existing methods and FEM show that the proposed method can provide a good prediction of active earth pressure under this situation.It is shown that,the active earth pressures? distribution for limited soils is nonlinear.If the wall-soil friction angle 0°,increases,but and decrease with the increase in the aspect ratio of backfill;and when,the results are the same from Coulomb formulae.If 0°,,and are coincident with Rankine theory.