Journal of the Japan Society of Erosion Control Engineering, Vol.56,No.4,p.32-39,2003

Large‐scale landslide in Tsaoling induced by the 1999 Chi‐Chi earthquake in Taiwan

Hiroshi KAWABE,Setsuo HAYASHI,Kanji KONDO,Shinya NUMAMOTO Abstract
Some factors for the occurence of the large‐scale landslide in Tsaoling, induced by the 1999 Chi‐Chi earthquake in Taiwan, were discussed. The results are as follows:1) The three components of acceleration were all very large, and the predominant direction of the seismic ground motion agreed with the direction of the slope. 2) The geology is Neogene, i.e. relatively new strata, and the bedding planes are roughly parallel with the ground surface. 3) This slope was under the ground conditions that a landslide was apt to occur by stress release or gravitational creep. 4) The ground has been weakened by salt weathering. Especially, 3) and4) may be controlling the repetition of landslides in Tsaoling. Therefore,the observation of these phenomena may offer effective data for the prediction of next landslide.

Key words:the Chi‐Chi earthquake, Tsaoling, large‐scale landslide, Neogene