THE MECHANISM OF MOVEMENT IN THE SALESHAN LANDSLIDE 1983 IN CHINA

A big landslide of 3.5 × 10^7m^3 ccurred at the Saleshan mountain, Gansu Province, China on 7 th March 1983. It moved at a high speed (13-14 m
sec at average) and killed 227 persons and destroyed 585 houses.The landslide mass slid down from a steep slope and rode on the quaternary alluvium and moved over about 800 m until the Baxie river.Sassa, 1989 has developed a new high-speed high-sress ring shear apparatus to estimate the friction angle during the motion of large-scale landslides. We took the sample from the quaternary alluvium on which the Saleshan landslide moved. In use of this sample, the authors performed tests to estimate the shear strength during mation under rapid loading using the high-speed high-sress ring shear apparatus. This rapid loading tests presented a small apparent friction angle during motion in the Saleshan landslids.Sassa, 1988 proposed a new computer simulation model for the motion of landslides. This method was applied fur this Saleshan landslide using this measured apparent friction angle. The result almost reproduced the real motion of the Saleshan landslide.