9416366 Roth Twenty-three years after the 1971 San Fernando Earthquake, the 1994 Northridge, CA, Earthquake caused substantial damage to earth structures, water conduit systems, and electrical equipment of the Van Norman complex of the Los Angeles Department of Water and Power (LADWP); specifically the Lower and Upper San Fernando Dams, the Tailrace, and the Los Angeles Reservoir. Ground deformations were measured on four LADWP earth structures, and there were seventeen strong-motion recordings inside and around the LADWP complex. This well-instrumented site provides a special opportunity to study the permanent deformations and failure and the post-earthquake stability of liquefiable soils and earth structures subjected to severe (0.98 g) ground shaking. This project involves three institutions: the University of Southern California (Part I), Dames & Moore (Part II), and Case Western Reserve University (Part III). The objective is to analyze the ground deformations and failures in the Van Norman complex following the 1994 Northridge Earthquake; from both research and engineering-practice points of view, based on state- of-the-art field and laboratory measurements. Coordination of the three research teams is provided by the University of Southern California. The objective of Part I (University of Southern California) and Part II (Dames & Moore) is to compare the 1971 with the 1994 observations of ground motions, and to investigate the validity of nonlinear dynamic finite element analyses in well-documented field studies. The objective of Part III (Case Western Reserve University ) is to characterize the soil and to establish its liquefaction potential, using the unit energy method, at a number of sites in the Van Norman complex where field observations and measurements are available. The results will be assembled in a data base and made available to the engineering community, in addition to being used in Parts I & II of this project. It is expected th at this project will assist practicing engineers and regulatory agencies to evaluate the capabilities and limitations of available models for the seismic response of soils and earth structures. This action is to support Part II (Dames & Moore) of this collaborative research project. ***
