REPONSE DYNAMIQUE D’UNE PLAQUE DE CHAUSSEE RIGIDE REPOSANT SUR UN SOL INERTE SOUS L’ACTION DU TRAFIC

Abstract

This study deals with the soil inertia influence on the dynamic response of a plate for rigid pavements design. The pavement is modeled as a thin plate with finite dimensions supported by dowels and tie bars. The foundation soil is three-parameter one (Pasternak Vlasov soil type with the accounting of inertia). The moving traffic load is expressed as a concentrated load of harmonically varying magnitude, moving straight along the plate with a constant acceleration. The governing equation of the problem is solved using the Bolotin modified method. This allowed to determine the eigen frequencies and the wave numbers of the system. The dynamic response of the plate is obtained on the basis of orthogonality properties of eigen functions. By applying the load at the middle of the plate, the results showed that the displacements of the plate are not zero at the edges but are lower than that of the middle of the plate. Furthermore, it is noted that the response of the plate is delayed parallel to the x axis due to the effect of the damping. It is also notice that, some significant gains can be obtained by taking into account the soil inertia in roads engineering design because the soil inertia reduce the plate response.