Application of Synthetic Aperture Focusing Technique to visualize GPR data from reinforced concrete structures

Ground Penetrating Radar (GPR) has been proven to be the most effective technology for imaging and evaluating the condition of concrete structures. That said, this paper presents an algorithm to automatically visualize GPR data collected from reinforced concrete structures. Specifically, the algorithm is based on the synthetic aperture focusing technique (SAFT) and is executed with two GPR data sets collected in a perpendicular survey grid. In the first step, for each scan line in a data set, a B-scan is reconstructed from the corresponding raw data using the SAFT technique. In the second step, the linear interpolation is employed, for each data set, to generate missing information between B-scans and create a 3D image of the surveyed object. Finally, by retaining the maximum amplitude of each corresponding voxel in the two images obtained from the second step, a combined 3D model is created.