The impact of a PEER funded research project “Next Generation Liquefaction: Japan Data Collection” is highlighted below. The project Principal Investigator is Steven L. Kramer, University of Washington. The research team includes Mike Greenfield, Graduate Student Researcher, University of Washington.
Soil liquefaction causes damage to buildings, bridges, pipelines, and other elements of the built and natural environments during earthquakes. Because few sites underlain by liquefiable soils are instrumented with strong motion seismographs, ground motions at liquefaction case history sites must usually be estimated from nearby recordings, ShakeMaps, or GMPEs. Sites at which ground motions were recorded on the surface of profiles that liquefied offer the potential, through careful interpretation of time-frequency analyses, to determine the level of shaking at the time liquefaction was triggered. These case histories are fundamentally different than most case histories, which offer a binary indication of whether liquefaction did or did not occur under an estimated level of shaking. Existing case history databases are incomplete with respect to many conditions for which geotechnical engineers are often required to evaluate liquefaction potential. These include liquefaction at depth, liquefaction of relatively dense soils, and liquefaction of gravelly soils. The three case histories investigated as part of this project will add to the sparse existing data for those conditions and their interpretation will aid in the validation/development of predictive procedures for liquefaction potential evaluation.