RESEARCHES ON SEISMIC LANDSLIDE STABILITY ANALYSIS

The origin,development and problem of seismic force analysis methods for slope stability are described in this paper. The codes of seismic analysis for the stabilization of slopes and landslides based on pseudo-static analysis were compared,and then some questions such as the magnified effect and coefficient of acceleration distributions,the rigid and non-rigid of landslides models,and the static and dynamic analysis were discussed. Pseudo-static analysis is one of the commonly used methods put forward firstly by Terzaghi K. However,it was questioned by scholars including Terzaghi himself from the start. Since Seed H.B.study systematically on the damage of earth-rock fill dam triggered by San Fernando earthquake on February 9,1971,the time-depended dynamic analysis has made significant progress and became the more scientific and logical method in Europe and America. The method in the Building Codes in Earthquake Region of the former Soviet Union in the 1940-1950s and the Chinese Specifications for Seismic Design of Hydraulic Structures(SDJ10-78)enacted in the 70s were still being used in the landslides codes formulated and revised after the Wenchuan earthquake,and the design theories and practical application are still at the primary experience stage. The authors suggest that new theory and methods should be recommended for reference to promote the modernized and standardized management of landslide seismic force analysis in China. That is,as the stability evaluation of landslide under the gravity should be classified to circle slice method and broken-line method according to the characteristics of rock and soil,the stability analysis of slopes under seismic load should be classified too:(1)for rockslides,pseudo-static analysis with amplification factor of earthquake inertia force distributed along the height should be preferred; (2)for saturated homogenous soil landslide,dynamics analytical method considering liquefaction feature under cyclic loading should be preferred; (3)for rock-soil accumulation landslides,pseudo-static or dynamic analysis methods with simplified amplification factor are generally to be preferred according to the landslides conditions.