Long Term Performance of Grouts and the Effects of Grout By-Products

This paper sets out a brief case history of the design of a cement-bentonite cut-off wall grout for use in very aggressive groundwater conditions and presents a basic procedure for the estimation of the design life of a grout barrier under such conditions. The paper then considers two perhaps unexpected effects of grouts, the formation of a soap-like material in silicate grouted ground which hindered slurry tunnelling operations and the release of ammonia from jet grouted ground.