Mathematical Analysis of Pipelines Located Through Both Liquefied and Non-Liquefied Ground

The earthquake damage data in the 1964 Niigata Earthquake and the 1983 Nipponkai-Chubu Earthquake show that the pipeline damage were found near the boundary between the liquefied and non-liquefied areas. In this paper, main factors affecting the pipe failure located through both liquefied and non-liquefied ground are considered in connection with subsidence, buoyancy and seismic motion which is different from the motion of neighboring sites. Formulae obtained by using beam theory are presented and the response characteristics of pipelines are discussed. The results suggest that serious attention should be paid to vibration-induced strains during liquefaction.