Nonlinear analysis of buried restrained and unrestrained segmental pipelines subjected to permanent ground deformation

The most common water distribution pipelines in the U.S. are segmental pipes and past major earthquakes have clearly revealed that the segmental water supply network is one of the most vulnerable civil infrastructure systems. To help gain better understanding of segmental pipelines seismic behavior a finite element model was developed and verified successfully. Then it was used to study the behavior of segmented pipelines subjected to distributed permanent ground deformations in both the axial and transverse directions. It was found that in general axial ground deformations cause more damages (e.g. joint separation) and restrained pipelines produced better results. A simplified method was then proposed to analyze the segmented pipelines. The close comparison between the results given by FE analysis and the proposed simplified approach suggest that the simplified approach can be effectively used to study the behavior of segmented pipes.