PREFACE

All of us interested in high strength concrete are indebted to the organizers and sponsors of the First International Symposium on Utilization of High Strength Concrete held in Stavanger, Noway, June 15 to 18, 1987. Experts in high strength concrete from throughout the world came together to discuss engineering developments and utilization of high strength concrete. Ideas and applications discussed during this meeting were widely reported and served as the basis for even greater utilization of high strength concrete in the future. This first symposium was sponsored by the Norwegian Concrete Association, the Norwegian Society of Chartered Engineers, the Federation internationale de la Precontrainte (FIP), and The Norwegian Institute of Technology, Cement and Concrete Research Institute.

The Second International Symposium on Utilization of High Strength Concrete was held in Berkeley, California, U.S.A., May, 1990. A substantial amount of research work and project construction with high strength concrete was completed in the period between the two symposiums, and many recent findings were presented and discussed at this most recent meeting. We are particularly pleased with the breadth of discussion, ranging from structural design issues to materials selection, construction methods, and repair techniques.

The participants were surveyed to identify areas of consensus and areas where additional research is needed. There is a clear consensus that high strength concrete is exceptionally durable and readily obtainable in commercial practice. Use of siIica fume, blast furnace slag cement, and other mineral and chemical admixtures can be particularly helpful in achieving the desired properties for the concrete. But, appropriate test methods need to be developed and we need a better understanding of in situ mechanical properties and overall structural ductility.

The Second International Symposium was co-sponsored by the University of California, Berkeley, California, U.S.A.; the American Concrete Institute (ACI), Detroit, Michigan, U.S.A.; the Precast Prestressed Concrete Institute, (PCI), Chicago, Illinois, U.S.A.; and Canada Centre for Mineral and Energy Technology (CANMET), Ottawa, Canada.

This volume is a collection of the papers presented at the Second International Symposium. More than 50 papers were received from throughout the world and reviewed in accordance with American Concrete Institute policies. The cooperation of authors in preparation of their manuscripts, patient consideration of referee comments, and careful revision of their manuscripts is greatly appreciated. To those authors whose submissions could not be included in the symposium, the organizing committee extends its strong appreciation for their interest and hard work.