Evaluation of Expansion in ETF Grout Compositional Variants

Abstract

In summary, the Base Case grout, Mix K, prepared according to the protocol provided (short stirring time after struvite precipitation of about 30 minutes) expanded when cured in a dry and damp sealed bag. Two variants, Mix M, 100 % slag in the dry mix, did not expand when prepared and cured under the same dry and damp conditions. Mix L, precipitated struvite removed, showed very slight expansion after curing 289 days for both dry and damp curing which was expressed as slight bulging at the bottom of the container. Mix N, 100 % dilution of the simulant, did not expand when cured under dry conditions or in a sealed container in damp conditions. However, a cylinder of Mix N cured in a container that was slit and taped back together did expand in damp conditions. This condition enabled the grout to be exposed to more moisture that the grout sample cured in the capped container and stored in the same zip top bag with the damp towel. This information is provided to support processing and containerization of the ETF ammonia grout.