GI-6Civil Engineering Applications of Ground Penetrating Radar
|Convener: Andrea Benedetto | Co-Convener: Lara Pajewski|
This Section is focused on the application of Ground Penetrating Radar (GPR) to civil engineering problems.
The GPR is extremely useful in producing high-resolution images of the subsurface, typically from 0 to 10 m depth, through wide-band nonsinusoidal electromagnetic waves. The employed frequencies range from 10 MHz to 4 GHz.
This survey method is effective, rapid, nondestructive and noninvasive. In fact, the GPR has become an established and powerful tool for the inspection of road and highway pavements, bridges, tunnels, and for detecting subsurface cavities and voids. It is also used to perform detailed quality controls of reinforced concrete. The GPR is very often employed for the
analysis of geological structures, for the mapping of soil, rock or fill layers in geotechnical investigations, and for foundation design, besides being a valuable monitoring technique of buried utilities as conduits, electricity cables, gas and water pipes.
Radars solve inverse problems, to estimate the electromagnetic properties of a target from field measurements. At present, different algorithms are employed to post-process collected GPR experimental data: most of them need a fast and accurate forward-scattering solver, to perform repeated evaluations of the scattered electromagnetic field due to known targets, and to be used in combination with some optimization techniques.
To obtain the best results, the GPR has to be correctly applied by qualified personnel, familiar with both the physical principles of the method and its limitations. The interpretation of resultant data is a difficult problem and should be carried out consciously and carefully, combining the relevant
information of above ground and subsurface features.
In this framework, the Session is concerned with the state of art, research activity, and progress of GPR techniques in civil engineering. In particular, novel georadar instrumentation will be presented. The outcomes of performed surveys will be reported. How to correctly plan experimental campaigns and conduct field measurements will be discussed. Direct and inverse electromagnetic scattering techniques will be a subject of interest, data processing methods and approaches for the interpretation of results will be proposed. Trade-offs between GPR and other nondestructive testing techniques will be considered. The merits and limitations of current GPR systems in various civil engineering applications will be highlighted.