GNGTS 2015 - Atti del 34° Convegno Nazionale

Park S.K. and Van G.P.; 1991: Inversion of pole-pole data for 3-D resistivity structures beneath arrays of electrodes. Geophysics , 56 , 951-960. Stummer P., Maurer H. and Green A.G.; 2004: Experimental design: Electrical resistivity data sets that provide optimum subsurface information . Geophysics, 69 (1), 120-139. Szalai S., Koppán A., Szokoli K., and Szarka L.; 2013: Geoelectric imaging properties of traditional arrays and of the optimized Stummer configuration . Near Surface Geophysics, 11 (1), 51-62. Van G.P., Park S.K. and Hamilton P.; 1991: Monitoring leaks from storage ponds using resistivity methods . Geophysics, 56 , 1267-70. Wilkinson P.B., Chambers J.E., Lelliott M., Wealthall G.P., and Ogilvy R.D.; 2008: Extreme sensitivity of crosshole electrical resistivity tomography measurements to geometric errors . Geophysical Journal International, 173 (1), 49–62. Wilkinson P.B., Loke M.H., Meldrum P.I., Chambers J.E., Kuras O., Gunn D.A., and Ogilvy R.D.; 2012: Practical aspects of applied optimized survey design for electrical resistivity tomography . Geophysical Journal International, 189 (1), 428–440. Zhou B., and Dahlin T.; 2003: Properties and effects of measurement errors on 2D resistivity imaging . Near Surface Geophysics. 1 (3), 105–117. GROUND PENETRATING RADAR APPLICATIONS FOR ROADS AND AIRPORT PAVEMENTS INVESTIGATIONS A. Mocnik 1,2 , M. Dossi 1 , E. Forte 1,2 , R. Zambrini 2 , A. Zamariolo 2 , M. Pipan 1,2 1 Department of Mathematics and Geosciences, University of Trieste, Italy 2 Esplora srl, academic spin-off of the University of Trieste, Italy Introduction. In this work we present three examples of application of Ground Penetrating Radar (GPR) method for pavement thickness evaluation and stratigraphic analysis using R.Ex. (Road Explorer), a new system developed by Esplora srl, an academic spin-off of the University of Trieste, in collaboration with the geophysical group of the Department of Mathematics and Geosciences of the same University. The implementation of this GPR system aims to obtain information that are crucial for the good management and planning of road maintenance, which is fundamental to prevent and minimize the risks to which light and heavy vehicles may be exposed during transit, and ensure the maximum safety for passengers. Nowadays, for testing of pavement of new road infrastructures, direct measurements such as drill cores are performed. Usually drillings reach a depth of about one meter from the road surface and its lateral spacing is variable, basing on the importance of the road and its constructive characteristics, but typically it exceeds some hundreds of meters. These surveys are primarily aimed at: • evaluating the thicknesses and local thickness variations; • collecting all the elements for the definition of the mechanical properties of the road pavement; • identifying voids, fractures or local defects; • evaluating the correspondence between the design specifications and the actual work. Similar surveys are also carried out even after the realization of significant works of maintenance of existing infrastructures or where particular problems have been reported on specific segments of a road infrastructure. In recent years, such direct investigations, which are necessarily destructive and require the partial or total road block, have been joined with other surveys globally defined as “ indirect ” that let to obtain information about the subsurface without coring, being not-invasive and not- destructive methods. These methods are used for the extraction of elastic properties of the substrate and aggregates layers as Falling Weight Deflectometer - FWD (Briggs et al. , 1991), 106 GNGTS 2015 S essione 3.2