Accuracy of data acquisition approaches with ground penetrating radar for subsurface utility mapping

Ground penetrating radar (GPR) is widely used in subsurface utility mapping for extracting the position (x, y) and depth (z) information of the utility. This information is crucial for subsurface facility management, in particular as reference in excavation works. The locational and depth information of the utility features is therefore of very important in subsurface mapping, apart from the reliability of the entire data acquisition and information retrieval method. This study investigates the effects of GPR data acquisition techniques to the locational and depth accuracy retrieved. The techniques examined are: (i) widely used perpendicular to pipe scanning; (ii) along pipe scanning; and (iii) variation angles scanning. Results indicated that along pipe scanning reported better penetrative power, higher detectability and best detection accuracy. Most importantly, this acquisition accuracy conforms to Quality Level A utility data requirements of the utility industries, hence offers the opportunities of GPR as measuring tool for underground cadastre system.