GPRS Scans Hollow Core Slab with GPR at Stadium - Gainesville, FL
GPRS was recently called out to a job-site at the University of Florida, where a basketball stadium was undergoing renovation. A general contractor working at the project contacted GPRS for help with locating post tension cables, and tendons in a hollow core slab. The contractors that were working at the job site were on a strict timeline, and they wanted to make sure that the planned renovations were completed before the upcoming basketball season.
Although we do not field many jobs involving scanning hollow core slabs, each of us at Ground Penetrating Radar Systems Inc., are thoroughly trained in diagnosing these types of slabs, as each of our Project Managers go though a multi-week trading course at the onset of employment.
Hollow core slab is a precast slab that has hollow chambers that run within the length of a slab. Between each hollow void, there are solid sections of slab that often have tendons at the top and/or bottom. These tendons are crucial to the structural stability of the slab. For this project, the customer was moving a volleyball court, and they needed to core drill the sleeves that would hold the poles for the new volleyball net location. Prior to the scan, the customer believed that half of the sleeves were going into a hollow core slab, and the others were going into a slab-on-grade.
Using our 1600MHz radar antenna, we were able to locate, and differentiate between the hollow sections of the slab and tendon-holding sections of the slab. The results of the scan allowed the customer to avoid in hitting any the tension cables by placing the sleeves in the hollow sections of the slab. Although the customer had far less concern for the sleeves that were thought to be going to be placed into the slab-on-grade, we scanned them anyway. Thanks to to this scan, we were able to inform the customer that the slab-on-grade also had hollow core, contrary to the previous information that they were provided. After mapping out the hollow sections, the customer was able to move the core locations and was able to avoid hitting any post tension cables.
GPRS takes pride in providing customers with the necessary data to minimize safety risks, and expensive mistakes that can easily happen when drilling or digging without proper sub-surface mapping. For this project, the customer made it clear to us that they were grateful for the information that we were able to provide to them.