Ground Penetrating Radar System, Inc. was contacted to scan an exposed grade beam that was to be removed at a Chrysler plant in Detroit, Michigan. We thought we were checking to determine the amount of rebar present in the beam (as is typical) but upon arrival, were that we were checking for conduit running in the beam.
Barton Malow was working to remove the beam and during the course of the demolition, a high voltage electrical conduit was exposed. There was nothing to indicate electrical was contained in this structural grade beam. Fortunately, no one was injured during this discovery. Barton Malow had used Ground Penetrating Radar System for concrete scanning on multiple occasions and the work was put on hold until the GPR survey could be completed to determine the presence of any additional electrical conduit.
The ground penetrating radar survey did confirm there were no additional electrical conduits in the concrete above the exposed conduit. We also checked the beam using Radio Detection, which can detect live power. Checking the depth of the conduit from the top of the beam gave the same approximate depth reading as the radar. Using these two methods to double-check the beam gave us a high level of confidence that there were no other conduits in the concrete above. This allowed Barton Malow to finish the job with the peace of mind, knowing there tradesman were in do danger of getting hurt while completing the demolition of this grade beam.
While the Ground Penetrating Radar project described above is slightly out of the ordinary for us, our company performs concrete scanning Ground Penetrating Radar surveys on a daily basis for determining the presence of electrical conduit prior to saw cutting and core drilling. We also use the Ground Penetrating Radar to determine the presence of voids below floor slabs and to determine the location of rebar and post-tensioning prior to core drilling.
Ground Penetrating Radar Systems performs work throughout the state of Michigan. John Kessinger is the director of Michigan Operations for Ground Penetrating Radar System and he can be reached at (734) 377-4551 or by e-mail at john.kessinger@gp-radar.com.
