08 May 2008
The Treviicos-Rodio joint venture, under a 36-month Design-Build contract, has used two barge-mounted Wirth PBA612 RCD (Reverse Circulation Drilling) rigs to construct a concrete cut-off wall for on W.F. George Dam, on theChattahoochee River, in the US. The cut-off wall, comprising an underwater secant pile section flanked by two land-side slurry wall wings, was necessary because of seepage problems. The RCD rigs were set above 137 mm diameter x 39.6 m long casings drilling to a depth of about 70 m from the top of the casing.