GPRS Scanning VS Classic X-Ray Technology
We recently received the opportunity to work for a customer who historically has relied primarily on classic X-ray technology rather than ground penetrating radar (“GPR”). They split their project between X-ray and GPR scan areas. By the time we finished the project, the PM contact encouraged us by telling us that they were very impressed with our results and that we would receive a lot more business from them in the future.
Here, I think are some of the reasons why:
Scheduling Flexibility: GPRS can generally mobilize to a site within 3 business days, and we can work day or night, with very little impact to the work around us. Classic X-ray produces harmful radiation that generally requires the work to be done at night with the building cleared. Because GPR uses much lower frequencies, it is as safe as a cell phone and does not require the space to be cleared.
Cost: Our total quote for this entire project was less than 20% that of our classic X- ray competitor. Because X-ray requires a film to be set up for each scan area, it is time and material intensive and thus more expensive.
Safety: When we first arrived on this project, we were informed that a conduit had just been hit when a pilot hole was drilled. X-ray technology requires that pilot holes be drilled blind, and that can result in the very damages that the technology seeks to avoid. GPR operates with zero destructive effect on the slab, and can be utilized from just one side of the slab.
Flexibility: In at least 6 areas, on this project, our customer had to change locations because of adjustments based on our initial findings. We were able to draw our results in real time and make these adjustments in real time, rather than adding a mobilization to scan the new areas.
Depths: 6 of the locations on this project were for pan drains that required chipping to 2"-3" into the concrete over a wide area. X-ray produces a 2D picture and thus cannot indicate the depths of items in the slab, but GPR can estimate depths to within about 10%. We were able to indicate depths, so those chipping out the pan drains would know how deep they could safely chip.
Line Tracing: As mentioned, on this project a conduit was struck with a pilot hole prior to our arrival on the site. We were able to quickly follow that conduit to the floor boxes on either side. We were able to trace the conduit for about 100 linear feet in less than an hour. This task would have been nearly impossible to X-ray.
Clean and Clear Markings: GPRS strives to lead our industry with clean and clear markings of our findings. One reason that contractors sometimes avoid GPR is that some GPR companies have confusing marking systems that make little sense. We strive to mark findings in such a way that there is no possible room for misinterpretation of what is occurring. Here are a few examples of our markings from this project: Because our marking are drawn directly onto the concrete (unless otherwise requested), they provide a lasting record that can be utilized if changes need to be made later in the project.
Because our marking are drawn directly onto the concrete (unless otherwise requested), they provide a lasting record that can be utilized if changes need to be made later in the project.
If you are ready to give GPR a try, or if your current GPR provider does not mark out their findings in a way that is easy to understand and discern, then please give us a call at 214.471.9001
GPRS does not provide geophysical, geological, land surveying or engineering services. If you need such services, please contact an appropriate professional.