Analysis of GPR and FWD Data Dependency Based on Road Test Field Surveys

Abstract

Ground penetrating radar (GPR) has been one of the most potent nondestructive techniques used in the diagnosis of roads over the years. Nowadays GPR is mostly used for determining layer thicknesses. The falling weight deflectometer (FWD) technique, which is used for elastic moduli determination, is time-consuming, discontinuous, and requires traffic restrictions. Layer thickness information should be obtained through coring or project documentation. Recently, GPR and FWD techniques have been used in combination where layer thicknesses from GPR scans are used as an input for FWD measurements in order to back-calculate the elastic moduli of the layers. However, inferring mechanical properties from dielectric properties are seldom targeted for the combined use of these two nondestructive techniques. The specific objective of this paper is to determine the possible relationship of FWD pavement deflections and GPR data based on road test field surveys. The relationship between GPR and FWD data in compliance with mentioned assumptions and conditions is quantified. The authors believe that the described relationship confirms the usefulness and eligibility of using GPR in connection with FWD as a tool for predicting the mechanical properties of materials, hence facilitating road diagnostics and minimizing the demands for traffic restrictions.