Masonry arch bridges evaluation by means of GPR

Some masonry arch bridges in Galicia (NW Spain) were surveyed with GPR using 250 and 500 MHz antennas. The main goal of this work was to perform an analysis of historical bridges, obtaining information about filling material homogeneity, detecting inclusions of different materials, defining structural faults -such as internal voids or cracks- and detecting ancient features -as hidden arches or previous profiles of the bridge-. Geometric 3D models of the surveyed bridges obtained with Laser Scanning methods, were used as inputs to create synthetic radargrams through FDTD simulations in order to help GPR data interpretation.