Pipeline Response to Seismic Displacement at Balboa Boulevard during the 1994 Northridge Earthquake

Abstract

Seismic displacement at Balboa Boulevard during the 1994 MW 6.7 Northridge earthquake ruptured a high-pressure natural gas transmission pipeline, a natural gas distribution line, and two pressurized water trunk lines. Three other natural gas transmission pipelines and an oil transmission pipeline were not damaged. This paper presents the available geologic, geotechnical, and groundwater data at the site and summarizes past research efforts studying the seismic displacement during the Northridge earthquake. Characteristics and engineering properties of the pipelines and the soil–pipeline interface, including data not previously published in the public domain, are investigated and summarized. The pipe strains are estimated using an analytical model that accounts for the soil displacement pattern, nonlinear stress–strain characteristics of the pipe steel, and effects of bends and elbows. The expected pipeline performance compares well with the observed performance.