Edwardsport IGCC Project

Edwardsport, IN

The Edwardsport IGCC Project involved the installation of 779 drilled shafts ranging in diameter from 3’ to 5’ with lengths ranging from 19’ to 53’. One particular site characteristic made this project unique; the new power plant footprint sat directly upon an abandoned coal mine. Even though the mine had previously been completely grouted under a separate contract, its presence allowed for unique considerations to be factored in during the design phase. Due to seismic activity concerns it was determined by the engineering team that no frictional design component associated with the mine’s five to twelve foot grout layer could be used in our drilled shaft design. Osterberg Cell Load Tests were installed and conducted to determine actual ultimate design values. Additionally, strain gauges above and below the grouted mine zone were used in the testing procedure to isolate the grouted mine zone layer’s frictional value for use in the final design. This extensive load test program provided actual in-situ design values ultimately allowing for the most efficient cost effective design solution for drilled shaft construction to be implemented.