Ground Penetrating Radar Systems, LLC (GPRS) of Michigan was contacted by a major national general contractor to locate rebar, conduits and post tension cables within the concrete flooring of a new multi-tenant high-rise project in downtown East Lansing, Michigan. The project remains under construction; however, several ground floor tenant spaces have been leased out and are undergoing site specific modifications which include embedding anchors, concrete saw cutting and coring.

In this sensitive project, it was important that the locations and depths of all reinforcing such as post tension cables, rebar, and conduits be located, to ensure that they would not be damaged during embedding anchors, concrete saw cutting or coring.

With Ground Penetrating Radar Systems' trusted history of accurately locating post tension cables and structural steel within concrete on several previous projects for this major contractor, GPRS was immediately called upon for this urgent work. GPRS arrived on site the same day the request was received. However, upon arrival to the project, ground penetrating radar could only “see” to approximately 4.0 inches. Based upon the GPR technicians 20 years of experience, it appeared that a layer of foam was used in the engineering of the concrete to compensate for elevation changes. The GPRS technician advised the client that the upper 4.0 inches of concrete would have to be cut and removed as well as the foam. Prior to leaving the site, GPRS provided ground penetrating radar to ensure that conduits were not present in this upper 4.0 inches of concrete prior to saw cutting.

After the upper 4.0 inches of concrete were removed, GPRS returned to the site to provide illustrations marked directly on site in real time of rebar and post tension cables. It turned out that two of the contractors proposed core locations were positioned directly above a series of post tension cables. Once the GPRSs technicians’ findings were marked on the concrete surface, the contractor was able to relocate the cores to avoid compromising any structural integrity of the building or personal safety of workers.

Ground Penetrating Radar Systems, LLC. is very familiar with working closely with countless major commercial projects and contractors. Ground penetrating radar is a great tool to scan areas for post tension cables, rebar, and conduits, including PVC pipes. Ground penetrating radar can also be used to locate underground utilities such as water, gas, electrical, communication, sewer, and other objects prior to digging or excavating. Please contact Ground Penetrating Radar Systems – GPRS to learn how we can assist with your next project.

GPRS has done many projects such as this in Lansing, Grand Rapids, Kalamazoo, Jackson and throughout the entire state of Michigan and performs GPR surveys throughout the United States. Contact Brian Chmielewski (Senior Project Manager) at 517.512.0018 or brian.chmielewski@gprsinc.com to schedule an appointment or if you have any inquiries for your next project.

GPRS does not provide geophysical, geological, land surveying or engineering services. If you need such services, please contact an appropriate professional.