Seismic Assessment for Offshore Pipelines

Abstract

An international consensus on seismic design criteria for onshore pipelines has been established during the last 30 years. The need to assess seismic design for offshore pipelines has not been similarly recognized. The geotechnical hazard for a pipeline routed across steep slopes and irregular terrains affected by earthquakes are discussed in this paper. The integrity of both natural and artificial load-bearing supports are assessed. The response of the pipeline to direct excitation from soil or through discontinuous, sparsely distributed natural or artificial supports are commented on. Some applications are given in order to point out topical aspects and major design issues for currently operating offshore pipelines crossing seismic active seabeds.