Abstract
During the 2004 Mid-Niigata Prefecture earthquake, thousands of landslides were triggered, among them two large scale rapid landslides (Higashi Takezawa and Terano landslides) occurred within past landslide masses and dammed the river at the toe of the landslides. By using a ring shear apparatus, real earthquake wave loading test and cyclic loading tests were performed on the samples from the two landslides. The results revealed that those sand samples from both landslides can suffer from sliding surface liquefaction phenomenon, while the silt sample from Terano landslide showed no liquefaction failure, indicating that the sliding surfaces of these landslides must have been formed within the sand layer in the past landslides masses.
