ANALYSIS OF LOESS SEISMIC LANDSLIDES UNDER IRREGULAR SEISMIC LOADING

In order to clarify the mechanism of a lot of large-scale loess landslides having happened i Xiji County of China at the time of the Haiyuan Earthquake (Ms=۸.۵) in ۱۹۲۰, an irregular seismic loading time history was made, which simulated the grOund motion induced by the great earthquake in the site of Huihui Chuan Landslide. Undisturbed samples secured from the site were tested in the laboratory by means of a triaxial test equipment in both static and irregular dynamic loading conditions to determine the strength parameters. Results of slope stability analysis. based on these strength parameters indi-cated that the magnitude of acceleration necessary to induce sliding in the site was ۲۸۵ gals. This is shown to be coincident with the site investigating results of earthquake damage