Pavement Evaluation Using Ground Penetrating Radar

The objective of this project was to develop an efficient and accurate algorithm for the back analysis of pavement conditions measured by ground penetrating radar (GPR). In particular, more reliable information about the thickness of the asphalt concrete (AC) layer and the dielectric constants of the AC and base layers were obtained from the electromagnetic field measurements performed on roads using GPR. A brief introduction to the existing methodology for interpreting GPR images is reviewed, and the theory associated with electromagnetic wave propagation in layered structures is described. Utilizing the full waveform solution, algorithms for back analysis of pavement conditions were developed based on the artificial neural network approach and the frequency response function concept. Software called ''GopherGPR'' uses the GPR signal from one antenna to interpret the characteristics of the AC layer with no assumptions on material properties. Thus, the new technique has the capability of providing information not previously available.