SLIDING SYSTEM PREDICTING LARGE PERMANENT CO-SEISMIC MOVEMENTS OF SLOPES

The sliding-block model is used widely for the prediction of permanent co-seismic displacements of slopes and earth structures. This model assumes motion in an inclined plane but does not consider the decrease in inclination of the sliding soil mass as a result of its downward motion, which is the usual state in the field. For the investigation of the above effect, this paper considers the dynamic motion of a variant sliding system; a perfectly flexible chain sliding along planes with gradually gentler inclinations. The governing equation of motion of the new model is approximately derived and solved for a number of earthquakes. The cases of ground slips where the permanent displacement of the new model differs considerably from that of the sliding-block model are detected and an improved method predicting permanent seismic deformations is proposed.