Cracks in rigid pavements are a frequent and critical problem, which needs to be assessed to avoid deterioration and provide comfort and security. Control of damage requires the evaluation of cracks width and depth. Several laboratory tests were used in order to determine the ability of Ground Penetrating Radar (GPR) in the evaluation of damage under different controlled conditions. Those tests were focused in the analysis of different crack dimensions, changing the material inside the fractures and the orientation of the antenna with respect the crack axis. Results showed that the crack width increases hyperbolae amplitude, being the thinnest crack detected with a 2.3 GHz antenna, 2 mm thick. GPR B-scans were compared to images from computational models. Additionally, a field survey provided images according to the lab tests.