Effective implementation of ground penetrating radar (GPR) for condition assessment & monitoring of critical infrastructure components of bridges and highways.

PDFTech ReportMD-15-SHA-UM-3-11SHA/UM/3-11Ground penetrating radarStructural health monitoringCondition surveysPavement management systemsPrecast concreteBridge decksQuality controlMarylandMaryland. State Highway Administration. Office of Policy & ResearchGoulias, DimitriosScott, MichaelUniversity of Maryland (College Park, Md.). Dept. of Civil and Environmental EngineeringUS Transportation CollectionRecently Maryland State Highway Administration (SHA) started to explore use of Ground Penetrating Radar(GPR) technology to provide quantitative information for improved decision making and reduced operatingcosts. To take full advantage of the GPR capabilities, improved analysis techniques need to be developed andimplemented. The objective of this study was to assist SHA engineers, technicians, and decision makers intheir current effort to explore the use of GPR in assessing the condition of critical infrastructure componentsand to identify potential improvements in GPR data analysis. The research team closely interacted withrepresentatives from selected divisions of the Office of Materials Technology (OMT) to identify potentialGPR applications using existing equipment accessible to SHA, targeting critical high priority areas foranalysis and improvement. In regards to pavement structures, a new methodology was suggested to improvethe accuracy of GPR data analysis. The initial analysis and results indicated that Multi-scale Pavement GPRdata Analysis (MPGA) has significant potential to add value and accuracy to pavement thickness data used inpavement management and rehabilitation analysis. The MPGA results indicate that pavement thickness datatrends can be identified based on either automated or semi-automated procedures based on target variabilitylevels of thickness uniformity, and thus can be used to efficiently evaluate pavement material layers.Similarly, for bridge deck analysis, techniques such as migration imaging (for concrete cover depthmeasurement applications among others) and Fourier analysis of GPR waveforms (for qualitative bridge deckmoisture analysis) were used in addition to emerging techniques such as Short Time Fourier Transformanalysis (for anticipated quantitative moisture analysis) for improving GPR data interpretation. Migration andFourier techniques were illustrated corresponding to GPR data collected using a GPR array on selected bridgedecks in the Salisbury, MD area. When applied appropriately, such techniques can provide more reliableanalysis of bridge deck inspection than conventional means. In terms of precast concrete, this study has shownhow GPR can be used to address several of the inspections needed in precast concrete production, includingan evaluation of concrete cover depth, reinforcement location, and section thicknesses. The testing anddemonstration showed significant potential for quality control using GPR