Residual Strength of Sand from Dam Failure in the Chilean Earthquake of March 3, 1985

摘要

The slope failures at La Marquesa and La Palma Dams in the Chilean earthquake of March 3, 1985 were apparently due to liquefaction of loose sand layers near the base of the embankments. The dams were low structures (4 to 10 m high) and the horizontal movements were substantial. However, the configuration of the embankments after the failures suggests that the liquefied soil retained a small but significant strength after liquefaction occurred. The two cases of dam failure described are of special interest because they provide examples of the performance of very low dams, in which static stresses are quite low, under strong earthquake conditions and they also provide two additional studies to add to the relatively sparse record from which residual strengths of liquefied soil can be determined on the basis of field performance.