Call Ground Penetrating Radar before you
core drill to locate any conduits in the area.

After striking the conduit, Ground Penetrating Radar Systems was contacted and
located two electrical conduit lines.

Example #2: You can see four core drilling locations in this image.  The core on the right hand side of the picture is where the contractor was drilling on and elevated concrete slab and struck a conduit run in a “smurf” tube. 

After striking the conduit the building demanded that the contractor “x-ray” all of the other core drilling locations.  They contacted GPRS to come and use ground penetrating radar to scan 10 different core drilling locations. 

The black lines represent GPRS’ layout and process to determine the presence of the electrical conduit.  You can clearly see the two angled black lines indicating the location of the electrical conduit. 

For a small fee GPRS can ensure that you will not have any costly electrical conduit strikes.  The contractor, in this case, was told that there were no electrical conduits running in the concrete.  

Please contact your local GPRS representative for scheduling and pricing information.

There is no doubt that whenever you, as a contractor, look to saw cut or core drill on a post tension reinforced concrete deck you should have the cables located.  However, we consistently see the aftermath of people who try to cut corners and drill or cut based on construction plans or good luck.  The results can be dangerous and structurally hazardous to the structure.

The picture you see below is the results of such a person core drilling prior to locating the post tension cables.  The band of tendons have broken and spawled through the concrete rendering them useless and creating a repair nightmare.  There is no reason, with the current technological testing methods in place, to hit rebar let alone post tension cables. 

We at Ground Penetrating Radar Systems, Inc. specialize in locating all types of reinforcing steel while post tension cable is probably the most common. 

This is what a typical layout looks like after GPRS has completed its surveying process.  You can clearly see the location of the post tension cable (“PTC”), the top and bottom rebar (“TR”/“BR”) as well as a conduit (“CONDUIT”) streaking through the area.  It is then relatively easy to pick a location to drill without hitting anything in the concrete.

1. You can clearly see the multiple broken cables present in this band of tendons.
   
2. You can also see the original placement of the cables and how they have moved since they were broken.

This is what a typical screen shot of data looks like that contains both rebar reinforcing steel and post tension cables.

1. You can see the rebar peaks all across the top of the data shot.
2. You can see the post tension cable reactions evenly spaced along the middle of the data shot.