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Proceedings of the Eighth International Conference on Shotcrete for Underground Support, held in Campos do Jordão, Brazil, April 11-15, 1999. Sponsored by United Engineering Foundation, Inc.

This collection contains 24 papers discussing state-of-the-art technical improvements in the use of shotcrete for underground works. These improvements have resulted in reducing project costs, while at the same time increasing safety. Topics include standardization, durability, early-age shotcrete, new technologies in equipment, and design and construction. Local shotcrete experience with single-shell-supported tunnels for the Sao Paulo subway constructed 20 years ago and recent design concepts currently under review, along with shotcrete developments in other countries, provided an interesting evaluation of design and durability improvement of single-shell linings.