Guide to Fiber-Reinforced Shotcrete (ACI 506.1R-08)

Description

Fiber-reinforced shotcrete (FRS) is mortar or concrete containing discontinuous discrete fibers that is pneumatically projected at high velocity onto a surface. Continuous meshes, woven fabrics, and long rods are not considered as discrete fiber-type reinforcing elements in this guide.

This document provides information on fiber-reinforced shotcrete using synthetic and steel fibers. Topics covered include materials used, mixture proportions, production of shotcrete, testing procedures, performance of FRS, design considerations (including an example in the Appendix),specifications, and some examples of applications.1.3—Historical background FRS with steel fibers was first placed in North America early in 1971 in experimental work directed by Lankard, etal. (1971).

Steel FRS (SFRS) was proposed for under ground support by Parker in 1971 (Parker 1974). Additional trials were made by Poad in an investigation of new and improvedmethods of using shotcrete for underground support (Poad etal. 1975). Subsequently, the first practical applications ofSFRS were made in a tunnel adit at Ririe Dam, ID in 1973(Kaden 1977). Since that time, SFRS has been usedthroughout the world. Shotcrete using micropolypropylenefibers was first placed in Europe in 1968 (Hannant 1978).Macrosynthetic fibers for use in shotcrete were developed inthe mid-1990s and have been used in mining and slope stabi-lization projects (Morgan and Heere 2000)