Seismic Performance Classification of Hazard Resilient iPVC Pipeline Systems

As technological advancements improve water distribution systems’ ability to accommodate significant ground deformations associated with earthquakes, fault rupture, landslides, liquefaction-induced lateral spreading, and other natural hazards, municipalities and pipeline designers need a systematic method to define and classify the seismic response and capacity of new and developing pipeline systems. This paper reports on a subset of full-scale tests, performed at the University of Colorado Boulder’s Center for Infrastructure, Energy, and Space Testing, that identify pipeline response to permanent ground displacements. The testing was performed on 6-in. diameter DR14 iPVC pipe with several different mechanically restrained joints. The results focus on categorizing the axial response of each tested iPVC pipeline system into seismic performance classes. Currently, ISO 16134 is the only design standard that includes a seismic performance classification for pipelines. However, ISO 16134 only considers the axial capacity or connection force capacity (CFC) of earthquake-resistant ductile iron pipe (ERDIP) and does not consider other commonly used pipeline materials. Recent work has expanded on ISO’s performance classification to include other common pipeline materials such as thermoplastics and polyethylene. This study expands on these efforts and defines seismic performance classes for several iPVC pipeline systems by relating the systems’ seismic response to ERDIP systems that have performed well during past seismic events. The results of this study are intended to provide a framework for how various systems can be assessed for seismic response, ultimately supporting ongoing development of ASCE’s Manual of Practice on seismic design of water and wastewater pipelines.