GPRS was called
to our site after the general contractor had discovered that a number of
electrical floor boxes had been covered over during the concrete pour. The pour
was a 12” thick, elevated concrete slab. It was the objective of GPRS to scan
the elevated concrete slab and identify the location of the floor boxes that
had been mistakenly covered in the final pour. GPRS delivered in a huge way on
Using what is
called a SIR3000 head unit with a 1600MHz GPR antenna, the technicians quickly
got set up, calibrated the equipment to the specific slab they were on and
began to diagnose the conditions. They began by scanning large areas of
concrete to determine the structural layout of steel and other embedments in
the slab. After determining a typical rebar and post tension layout, they began
to hone in on the anticipated floor box locations as pointed out by the general
contractor. With each area cleared and ready to be GPR scanned, the GPRS team
was able to quickly identify electrical box number one. The GPR crew quickly
moved around the slab to scan and identify electrical boxes within the slab. In
total, GPRS located all 15 floor boxes that had been covered.
During the GPR
scanning process, GPR technicians had located a number of high priority
targets. Targets such as live electrical conduit, #4 rebar, post tensioned
cable and beams. Many of these features came as a surprise to the contractor on
site and it turned out to be extremely valuable information. Knowing where
these obstructions were in the slab potentially saved the project from undue
delays and injury if the drill crew would have drilled into one of them.
While on site,
the GPRS Project Manager had a new team member with him whom he was training.
When asked, GPRS was proud to discuss how thorough and valuable their training
program is and why it is critical for new hires to join the senior technicians
on job sites. The pair of GPRS technicians moved around the slab and discussed
the structural makeup of the building. The senior technician pointed to
features such as slab thickness, the columns and beams, fixtures hanging from
above and how those might help in identifying where the floor boxes might be,
and so on.
When the GPRS men
finished up, they approached our crew and asked if we could spare a minute to
walk the slab and discuss their findings. The technicians took the time to walk
to each location they had scanned and thoroughly discussed what they had found
in the slab and how to interpret the markings they had drawn. After reviewing a
few locations with them, we could sense the confidence they had in what they
had found and we immediately had piece of mind that our crew would be safe when
chipping out the floor boxes.
We were able to complete the procedure with
great success and recovered all 15 floor boxes. Thanks to GPRS, we are on to
the next phase of our project and we were able to save cost and time because of
the expertise of GPRS.