LIQUEFACTION ANALYSIS OF SILT INTERLAYERED SANDS BY MEANS OF A NUMERICAL METHOD

Abstract

Liquefaction phenomenon in sands during earthquakes is known to be the cause of many earthquake related damages including loss of bearing capacity, lateral flow and spreading, slope failures, etc. Therefore, a great deal of effort has been exerted in the past 40 years for understanding the mechanism of liquefaction and factors leading to liquefaction in the field. Field observations in recent earthquakes, including 1999 Kocaeli Earthquake in Turkey, have pointed out that silt inclusions and bands in the sandy deposits can have a significant effect on development of liquefaction. In this study, the behavior of sand deposits with and without a silt interlayer has been numerically analyzed using a computer code named LASS IV. It is also shown that taking into consideration the effects of two horizontal components of an earthquake rather than one can significantly increase the probability of occurrence of liquefaction and its extent of depth. Also, the behavior of an instrumented test site is numerically analyzed and the results are compared with the recorded behavior.