DRUM CENTRIFUGE TESTS ON WAVE-INDUCED LIQUEFACTION AND SINKING OF SUBMERGED RUBBLE MOUND

Abstract

 This paper discusses the experimental findings pertaining to the instability of the submerged rubble mound on sand bed due to wave-induced liquefaction in sand beds. The emphasis of the experiments was placed on investigating the relation between the occurrence/propagation of liquefaction and the development of sinking of rubble mound under the action of severe traveling fluid waves. A range of wave tests using a drum centrifuge was performed under a centrifugal acceleration of 70 gravities. It was found that the rubble mound on the sand bed started sinking significantly upon the progress of liquefaction to the soil region below the mound in association with vibration of liquefied sand. The experimental results also show the importance of control of progress of liquefaction as a countermeasure of sinking of the mound.