Evaluation of Ground Penetrating Radar as a Tool in Designing Maintenance and Rehab Projects in Mississippi

A large portion of Mississippi Department of Transportation's (MDOT’s) construction budget is spent on maintenance and rehabilitation (M&R) of existing roadways. An important aspect of evaluating existing pavements during the design of M&R treatments is coring. Cores provide the designer an indication of pavement condition. Currently, cores are cut randomly or based upon visual observation of the pavement surface. A tool that assists the designer in selecting more appropriate core locations would provide the designer better data for the design. One such tool that may be of benefit is the ground penetrating radar (GPR). A GPR is equipment that transmits electromagnetic energy into the ground (or pavement). When this energy encounters a discontinuity within the pavement structure, the energy is reflected or refracted back toward the surface. A receiving antenna then records the variations in the return signal. Because of its ability to identify these discontinuities within a pavement structure, the GPR has the potential of identifying pavement distresses or conditions that are not visible at the pavement surface. The objective of this study will be to evaluate whether the GPR can be used as a tool to assist an Engineer design M&R treatments by better identifying questionable areas for further evaluation.