GPRS (Ground Penetrating Radar Systems Inc.) was hired by Ohio State University (OSU) to locate utilities running through their laser labs, inside their robotic welding and additive manufacturing research building. GPRS was able to locate utilities running through the area, as well as the type of reinforcing within the concrete and the concrete slab thickness.

Pictured here is a GPRS Project Manager scanning in front of Ohio State's new robotic laser welding system, the installation of which would not have been possible without quality ground penetrating radar scans provided by GPRS. This robot will be used for cutting edge robotic welding and additive manufacturing research. The system features a 6 kilowatt laser head equipped with the latest laser beam raster and waveform technology, as well as a wire arc system enabling extremely high productivity hybrid laser-arc welding.

GPRS’s findings changed OSU’s plan regarding placement of the lasers. GPRS was able to highlight possible structural integrity issues as well as locate utilities near the proposed locations. For example, the concrete was reinforced with wire mesh, rather than rebar, which is preferable for such heavy equipment. OSU is now conducting research into how they could increase the structural integrity of the areas where the lasers are due to be placed. Without GPRS, these lasers may have been bolted to inappropriately reinforced concrete.

One of the benefits of calling GPRS for any concrete scanning or utility locating job is that we are specially trained in more than one method and utilize several different pieces of equipment to ensure our customers receive the most thorough and all-encompassing methodologies to perform our jobs to the highest standards possible. This was particularly useful in this project because some utilities could only be located with GPR and some could only be located using the Electromagnetic Pipe Locator.

The 1600 MHz and 2000 MHz GPR Antennas work by sending pulses of energy into a material and record the strength and the time required for the return of the reflected signal. Reflections are produced when the energy pulses enter into a material with different electrical properties from the previous material. The strength of the reflection is determined by the contrast in signal speed between the two materials. The total depth achieved can be as much as 18 inches or more with each of these antennas but can vary widely depending on the conductivity of the materials and other factors such as the spacing of the reinforcing. The Electromagnetic Pipe Locator can passively detect the electromagnetic fields from live AC power or radio signals traveling along some conductive utilities. It can also be used in conjunction with a transmitter to connect directly to accessible, metallic pipes, risers, or tracer wires which was what we did in this instance.

Had GPRS not had both these technologies to hand, we would not have been able to find every utility whilst gaining structural information about the concrete. Please contact GPRS for any of your utility locating or concrete scanning needs; Daniel O’Shea: 614-202-8553 daniel.oshea@gprsinc.com, Mitch Streight: 614-400-6889 mitch.streight@gprsinc.com.

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