Many infrastructure enhancement projects require underground utility mapping before starting any excavation processes, especially in urban areas. In fact, mapping of an area provides a general overview of the infrastructure above and underground. This mapping can be done by Ground Penetrating Radar (GPR), which is commonly used as a Non-Destructive Testing (NDT) technique that allows, among others, the detection and localization of buried utilities without any damage to the surface. This paper presents the results of mapping sewer lines in an urban region of the city of Tunis, Tunisia, using GPR. In this study a ground-coupled GPR system with a frequency of 400MHz was used to detect and locate the sewer lines in the study area. In order to reduce the amount of collected data over the large study area, some subareas were selected where GPR testing was conducted and data were analyzed. Then, sewer lines were interpolated over the whole area using the GPR results and the locations of manholes visible from the surface. It was shown that using this technique mapping of the pipes in the entire area can be achieved. All data presented in this study were collected by the Office of Topography and Cadastre (OTC) in Tunisia.

Ground penetrating radar (GPR) is a technique based on sending electromagnetic (EM) waves through the structure and then recording the reflected signals, which present at dielectric discontinuities into the structure. Peak detection of GPR data is important for the diagnosis of ground infrastructures. This paper describes the application of lifting wavelet transform (LWT) to detect peaks in GPR signals. These peaks are used to calculate the two-way travel times t_i of the EM waves between the antenna and the layers i. Then distances d_i are calculated from these times. The measured values (distances) are compared with the manually determined values. The performance of peak detection with Lifting Wavelet Transform was evaluated by computing the mean absolute percentage error (MAPE). The results clearly indicate that this method is perfectly able to estimate thickness within 14.27%, mean average error rate which justifies and validates the model used.

This paper proposes a method to estimate three parameters: the radius, the depth of buried empty cylindrical tubes and the dielectric constant of the surrounding medium, by Ground Penetration Radar (GPR). These parameters are detected and characterized by radargrams. Those radargrams contain a parabolic shape that indicates the presence of target. This is can be achieved through two major phases: the processing stage of the electromagnetic (EM) signals which are received by the GPR. This stage is followed by another one which is the fitting curve of the parabolic shape appeared in the radargram. Finally, the results clearly indicate that this method is perfectly able to estimate the depth within 1.66%, mean average error rate and the relative permittivity of the emulsion of 3.41% and that the radius of 29.52%, whish justify and validates the model used.

Ground penetrating radar (GPR) is a method founded on sending electromagnetic waves which are transmitted from an antenna and reflect off layers or objects in the earth. GPR is used to detect objects buried in the ground and predict their depths, such as landmines, pipes and cables or any other dielectric material. GPR gives information about the ground infrastructures throughout the scanning of the surface to be examined. In this paper GPR method is used to determine the depth and diameter of the buried tube. The method is based on the analytic signal which is used to extract the signal envelope of GPR data to estimate the depth and the diameter of underground tube. The measurement value is approximately coherent with the real value. This proposed method achieves good result.

Ground‐penetrating radar (GPR) is a non‐destructive technique used to assess the subsurface and locate any buried objects such as subterranean utilities. It emits electromagnetic radiations and detects the reflected signals from underground objects. Nevertheless, many GPR acquisition factors cannot easily be accounted for in evaluating the performance of the GPR system. To ensure more correct and accurate detection of the GPR signals reflected by a buried cylindrical object in a homogenous medium, sensitivity analysis of GPR data is proposed in this work. The numerical simulator gprMax, which is based on finite‐difference time‐domain, is used to generate GPR data. The data analysis results showed that the GPR measurement accuracy is more sensitive to the incident signal waveform than the other parameters. Thus, one of the major characteristics of GPR that can affect its accuracy is the incident waveform.