Signature Failure Modes of Pipelines Constructed of Different Materials When Subjected to Earthquakes

The 2010/2011 Canterbury (New Zealand) earthquakes caused significant damage to buried pipeline infrastructure. Observations of damaged pipes that were made during either repair or replacement were used to define representative examples of the damage to each of the commonly used pipe materials. The different pipe materials that were considered included steel reinforced concrete, polyvinyl chloride, high-density polyethylene, cast iron, asbestos cement, and vitrified clay. Photographs of damaged pipes at the time of repair were collected and analyzed to identify pipe failure modes. It was determined that different pipeline materials exhibited different failure mechanisms during the earthquakes and that each pipe material was found to have a distinct failure signature. In particular, polyvinyl chloride pipes behaved in an unexpected brittle way. The failure mechanisms of each type of pipe are described using engineering nomenclature, and the signature failure modes are categorized and tabulated to facilitate comparison between the differing pipe materials.