Ground Penetrating Radar Systems was recently contacted to locate reinforcing steel in slab on grade at a popular Resort & Spa in central Florida. The rebar in the concrete slab of the pool floor was suspected to be too close to the surface of the slab, therefor causing rust stains on the pool floor surface when the rebar got wet. Facilities management called on GPRS, LLC. to help locate thea steel to determine if it was the cause of the surface staining.

After draining the pool down just a couple of feet, GPRS technicians were able to locate the existence and location of rebar within the slab and mark them out directly on the dry surface of the concrete with blue tape. The concrete at this location was found to be approximately 9-10” thick with rebar throughout on 12” centers at approximately 5-7” deep. The GPR equipment provided by GSSI is designed to scan on most surfaces provided that they are dry to mark on and are fairly flat. The ability to identify where the steel was placed in this slab was very beneficial for the crew as they now had the information to determine what might be causing the surface staining.

The equipment used in the scan was a four-wheeled, handheld cart carrying a 1600 MHz antenna capable of identifying objects at a depth of approximately 24” deep. The antenna relays its signal to an SIR-3000 computer system which displays the geophysical data.