During the course of building a tower over eight hundred feet tall, numerous unforeseen issues are bound to arise, no matter how carefully things are planned. At Aqua Tower, a new condo/hotel complex in the Chicago Loop that will stand 835 feet at completion, James McHugh Construction has needed to work around many of these issues: sleeves have been missed, pipes have been moved, additional holes need to be drilled in unexpected places. This building is a cast-in-place concrete structure reinforced with a post-tensioning system. When these issues have arisen, McHugh has called Ground Penetrating Radar Systems to assist in locating post-tensioned cables, rebar, and conduits in order to enable these additional or relocated holes to be drilled safely.

GPRS representative Nathan Machel has worked with McHugh and several subcontractors to provide information necessary to drill approximately one hundred holes through ten-inch thick slabs. When anchors need to be set in post-tensioned floors, GPRS is able to locate the cables and provide an accurate depth, allowing anchors to be set safely. When the engineers need to confirm the placement of reinforcing steel, GPRS is able to provide the necessary data. In ways like this, Ground Penetrating Radar Systems helps the construction to proceed with increased safety and efficiency.

Concrete scanning with GPR for the purposes of locating post-tension cables, rebar, and embedded electrical conduits is a common application for GPRS. We plot the locations of the steel or conduit directly onto the concrete surface, in order for the drilling to be completed successfully without damaging a PT cable or shutting down electrical service.

Nathan Machel runs GPRS operations in Chicago. He can be reached at 847-514-2277 or by email at nathan.machel@gp-radar.com.