GNGTS 2017 - 36° Convegno Nazionale

GNGTS 2017 S essione 3.2 625 Acknowledgments The geotechnical analyses were performed in the laboratory of Applied Geology of the University of Perugia funded in the framework of the “ Ricerca di base 2014 Project – DIMBASE14 ”. References De Chiara, F., Fontul, S., Fortunato, E.; 2014: GPR Laboratory Tests For Railways Materials Dielectric Properties Assessment. Remote Sens., 6 , 9712–9728. doi:10.3390/rs6109712 Di Matteo, L., Bigotti, F., Ricco, R.; 2009: Best-Fit Models to Estimate Modified Proctor Properties of Compacted Soil. J. Geotech. Geoenvironmental Eng., 135 , 992–996. doi:10.1061/(ASCE)GT.1943-5606.0000022 Di Matteo L., Pauselli C., Valigi D., Ercoli M., Rossi M., Guerra G., Cambi C., Ricco R., Vinti G.; 2017: Reliability of water content estimation by profile probe and its effect on slope stability. Landslides (In press). Ercoli, M., Pauselli, C., Forte, E., Di Matteo, L., Mazzocca, M., Frigeri, A., Federico, C.; 2012: A multidisciplinary geological and geophysical approach to define structural and hydrogeological implications of the Molinaccio spring (Spello, Italy). J. Appl. Geophys., 77 , 72–82. doi:10.1016/j.jappgeo.2011.11.011 Ercoli, M., Pauselli, C., Frigeri, A., Forte, E., Federico, C.; 2014: 3-D GPR data analysis for high-resolution imaging of shallow subsurface faults: the Mt Vettore case study (Central Apennines, Italy). Geophys. J. Int., 198 , 609–621. doi:10.1093/gji/ggu156 Fetter, C.W.J.; 2001: Applied Hydrogeology - Fourth Edition. Prentice-Hall, 621 pp. Jol, H.M.; 2009: Ground Penetrating Radar: Theory and Applications. Edited by: Harry M. Jol, Copyright {©} 2009 Elsevier B.V., 543 pp., doi:10.1016/B978-0-444-53348-7.00007-7 Lambot, S., Rhebergen, J., Slob, E.C., Vanclooster, M.; 2004: Measuring the Soil Water Content Profile of a Sandy Soil with an Off-Ground. Vadose Zo. J., 3 , 1063–1071. Porretta, R., Bianchi, F.; 2016: Profiles of relative permittivity and electrical conductivity from unsaturated soil water content models. Ann. Geophys., 59 , G0320. doi:10.4401/ag-6990 Revil,A., Karaoulis, M., Johnson, T., Kemna,A.; 2012: Review: Some low-frequency electrical methods for subsurface characterization and monitoring in hydrogeology. Hydrogeol. J., 20 , 617–658. doi:10.1007/s10040-011-0819-x Topp, G.C., Davis, J.L., Annan, A.P.; 1980: Electromagnetic Determination of Soil Water Content: Water Resour. Res., 16 , 574–582. doi:10.1029/WR016i003p00574 Tosti, F., Slob, E.; 2015: Civil Engineering Applications of Ground Penetrating Radar, Springer Transactions in Civil and Environmental Engineering. Springer International Publishing, Cham., 371 pp. doi:10.1007/978-3-319- 04813-0 van Dam, R.L., Borchers, B., Hendrickx, J.M.H.; 2005: Methods for prediction of soil dielectric properties: A review, in: Detection and Remediation Technologies for Mines and Minelike Targets X, March 28, 2005 - April 1, 2005. pp. 188–197. doi:10.1117/12.602868 GPR investigation of columns in controlled conditions G. Gennarelli 1 , F. Soldovieri 1 , G. Leucci 2 , R. Persico 2 1 CNR-IREA, Napoli, Italy 2 CNR-IBAM, Lecce, Italy This contribution describes GPR experiments related to two cylindrical columns built close to the Institute for Archaeological and Monumental Heritage IBAM-CNR, office of Lecce, Italy. The investigation of cylindrical structures is of interest for the non-invasive diagnostics of monumental buildings (Leucci et al. , 2007), modern circular pillars made-up of reinforced concrete, or even tree logs (Butnor et al. , 2009). In particular, a GPR investigation is able to provide information about the possible presence of internal voids, fractures, metallic hinges or reinforcement rebars. When GPR data are collected along the height of the column, it is often acceptable to process the data as if they were gathered on a half-space, as done in (Leucci et al. , 2007). Anyway, it is also of interest to gather data along circular profiles at a fixed height (Santos-Assuncao et al. , 2014), that can provide clear images of the cross-section of the column or of the pillar. In this case, the ray of curvature of the investigated surface is usually of the order of the probing wavelength. As a result, it is not possible to exploit the model based on a flat surface, which is at the basis of most commercial codes for GPR data processing (e.g. Reflexw and GPRslices).