9612339 De Alba This action is to support a small workshop to examine how the value of the full-scale earthquake engineering experiment at Treasure Island, California, might further be enhanced. Treasure Island, an artificial island in San Francisco Bay, California, approaches ideal conditions for a full-scale field experiment to study the response of soft ground during strong earthquake shaking. It is located between the San Andreas and Hayward faults, on which a magnitude 7 or greater earthquake is expected to occur within the next thirty years, with a probability greater than 67%. The major instrumented site on the island, which is one of the National Geotechnical Experimentation Sites, is located on 300 feet of soil, including 40 feet of hydraulic fill sand, underlain by soft to hard clays. It is adjacent to Yerba Buena island, a rock outcrop, thus permitting motions of the rock outcrop, deep bedrock, and soil to be measured and compared. Currently, instrumentation at the "fire station" site on Treasure Island includes six accelerometers in a vertical array between bedrock and the ground surface, as well as six piezometers in the upper potentially-liquefiable hydraulic fill. The installation of these instruments (completed in 1993) was accompanied by an extensive site characterization program. Support for the Treasure Island National Geotechnical Experimentation Site has been a collaboration between the U.S. Navy, National Science Foundation, Federal Highway Administration, U.S. Geological Survey, California Division of Mines and Geology, Electric Power Research Institute and the University of California at Davis. The major questions to be addressed by this workshop are: What is the best use of strong motion information so as to improve or create models to predict the behavior of soft soils under strong ground motion? What additional site information is required? The goal of this workshop is to assure that all the major pieces of information are in pla ce at the time of the next major earthquake, so that the data obtained can quickly and efficiently be used by researchers, and thus lead to rapid development of improved techniques for predicting the behavior of soft soils under strong ground shaking. ***
