The gravity induced preconsolidation deformation of rock and soil has been finished before our consideration in many geotechnical problems. The stress field in soil mass is balanced with the gravity field. So in the FEM calculation that is based on the initial condition above

if the gravity is loaded directly

a rather big deformation will occur which should have been finished. So on the basis of initial stress load theory that is studied in this paper

an approach is proposed to exclude the preconsolidation deformation. The detailed procedure is provided by example at last and proved to be true.