WAVE-INDUCED LIQUEFACTION AND SINKING OF PIPELINES IN SAND BEDS IN A DRUM CENTRIFUGE

Abstract

 This paper discusses the experimental findings pertaining to the sinking of buried pipeline in association with wave-induced liquefaction in sand beds. The emphasis of the experiments was placed on investigating the relation between the liquefaction process and pipe behaviour. A series of wave tests using a drum centrifuge was performed under centrifugal accelerations of 70 gravities. It was found that the progressive liquefaction and progressive solidification were well reflected in the start of movement of pipeline and the end of sinking. Indeed, the pipe started moving downward upon the liquefaction front passing through the pipe location, and the sinking of pipe terminated, when the lower surface of the pipe met the solidification front advancing upwards.