9313848 Isenberg This action is for continued support of an experiment in which underground instrumented pipeline segments were constructed and installed in a zone of probable earthquake rupture in Parkfield, California. The overall objective is to investigate the damage experienced by buried pipelines due to strong earthquake shaking, and to use data measured during strong ground shaking to evaluate analytical models for predicting this damage. Since 1857, seven earthquakes have occurred on the San Andreas Fault in the vicinity of Parkfield, at an average interval of 22 years. The last earthquake was in 1966, and the United States Geological Survey (USGS) predicts, with a 95% confidence level, a recurrence before 1993. The choice of the site at Parkfield was made with assistance from USGS geologists. This experiment is supported in collaboration with the National Center for Earthquake Engineering Research in Buffalo, New York, and the Urban Earthquake Hazard Research Institute of the University of Tokyo in Japan. The first objective of this project is to investigate the effects of lateral offset on pipelines, a major damage mode, and to provide data on the relation between ground displacements and pipeline response in order to evaluate analytical models of this damage mode. The second objective is to investigate the damage induced by travelling seismic waves, another important damage mode, and to use measured data to evaluate analytical models. Whereas the first experiment requires that the surface rupture cross the installed pipelines, the second experiment is dependent only on the installation being subjected to strong ground shaking. ***
