Abstract：The main problem of raod constructed on soft-soil fundation is the subsidence resulted fromconsolidation of foundation. Uneven subidence has great effect on rigid pavement. In recent years,anew subject which met by highway engineerers is how to construct rigid pavement on soft-soil founda-tion. A mechanical model used for sandwich pavement structure is presented and a hindamental equa-tion based on the normal displacement is obtained. A finite element program named SANDWICH is de-veloped. Form field test and numerical computation, nomographs for calculating slab stresses were pre-sented. Example showed that this method can be used in practice.