A new procedure for determining the shear strength of sand for slope stability analysis. An earthquake is proposed together with a simplified procedure for predicting deformation in earthquake. The proposed method is based on the advanced total stress method and uses undrained strength of sand with consideration on strength anisotropy. Soil parameters required in the use of proposed method as well as for deformation prediction are indicated and then results of stability and deformation analyses with the proposed method are presented for a revetment constructed on a silty sand on Tokyo Bay together with 1) field and laboratory tests results, 2) results with the method currently authorized in Japan and 3) field behaviour of this revetment in the Chiba-Tohooki earthquake of 1987