Introduction of T. L. Youd

Abstract

Dr. Les Youd, Professor Emeritus of Civil Engineering at Brigham Young University, presented the Fifth Seed Lecture at a special session and banquet sponsored by the San Francisco Section of the Geo-Institute of ASCE in 2003. It is especially appropriate that Professor Youd was selected to present the Seed lecture, as he was a leading pioneer in the investigation and use of field performance case histories in geotechnical earthquake engineering, and his expertise and uncanny ability to distill and recall vital data and observations were highly admired by the late Professor Seed. Professor Youd received his BS degree in Civil Engineering from Brigham Young University, and his PhD from Iowa State University. From 1967 to 1984 he served as a Research Civil Engineer with the U.S. Geological Survey. In 1984 he joined the faculty of the Department of Civil Engineering at Brigham Young University, where he served as Chairman from 1994 through 2000. He retired formally in June of 2003, but continues to be actively involved as a Professor Emeritus. Professor Youd was an early leader in geotechnical postearthquake investigations, and has served as a member of postearthquake investigation teams following 11 major earthquakes on four continents. He established high standards for postearthquake studies, and these have been widely emulated, to the considerable benefit of the profession. He also set important standards for study of earlier, “historic” occurrences of seismically induced soil liquefaction. Professor Youd was a pioneer in the development of techniques for mapping of seismic soil liquefaction hazard, and he continues to be an important figure in this field. He has also developed widely used methods for prediction of liquefactioninduced lateral ground movements and corollary damages to