ACT was awarded the grout curtain contract through a Best Value Selection process (RFP) by the US Army Corps of Engineers Louisville District. The goal of the project was to reduce water seepage through the rock foundation of the dam to a value of 3 Lugeons by installing a 3 line grout curtain
Work included: overburden drilling and overburden casing installation, percussion rock drilling, initial exploratory drilling, borehole washing, water testing, pressure grouting, and final exploratory verification hole drilling. Extensive grout mix development testing was performed to obtain specific grout rheological properties for existing site conditions. Routine quality control testing maintained grout mix quality throughout construction. Cementitious grout mix formulations contained several grouting ingredients including bentonite, flyash, silica fume, welan gum, superplasticizer, and type 1 portland cement
To ensure that the project goal was achieved, real time computer monitoring of the grouting operation was performed utilizing electronic flowmeters and pressure transmitters linked to a xy-recorder and personal computer. Grouting parameters were displayed, analyzed and recorded in real time. As a result, the project goal of reducing the residual permeability of the rock to 3 Lugeons was accomplished.
Client: US Army Corps of Engineers, Louisville District
Owner: US Army Corps of Engineers, Louisville District