f Application of GPR to the construction of utilities

This paper presents how Ground Probing Radar can be used before laying shallow utility lines. The first reconnaissance problem is the selection of a path avoiding the other utilities present . The traditional methods have shortcomings which can be overcome by GPR : plans are inaccurate in location and depth, electromagnetic detection is inefficient for non-Metallic utilities . Another reconnaissance issue is geology, which governs the choice of laying technology, either open trench, impact moling or directional drilling . Trenchless technologies cannot work in some geological media and are sensitive to ground inhomogeneities. Geological raps are often meaningless at shallow depth in urban areas, while checking holes cannot provide continuity. GPR can detect boulders and underground masonry remains, as well as characterize the geologic media .