ANALYSIS ON BEHAVIOR OF SEISMIC TYPE DUCTILE IRON PIPES INFLUENCED BY GROUND DEFORMATION OCCURRED IN JAPAN

Abstract

 In Japan, earthquake or heavy rain have caused large-scale ground deformation. Therefore, buried water pipelines were damaged seriously. Seismic type ductile iron pipes have not been damaged and have passed water after large-scale ground deformation, because those joints have extension and contraction function, bend performance, and separation preventing performance. But there were few cases that seismic type pipelines were buried at the sites occurring large ground deformations. Ground deformations have been classified by type, such as liquefaction, embankment failure. And different type of countermeasures for ground deformation have been implemented for buried pipes. The pipeline behavior influenced by different type of ground deformation may show similar behavior, because the researches of behavior of pipeline influenced by ground deformations and the test to confirm behavior of pipeline influenced by ground deformations showed that some joints of seismic type pipeline extend, contract, or bend by following ground deformations. However, there are few study cases to compare the ground deformations by using the behavior of seismic type pipeline, without classification by type. In this study, we analyze the behavior of seismic type pipeline influenced by ground deformation, and consider whether it is possible to deal with different type cases of ground deformation as the same classification.