1. Associate Professor, Dept. of Structural and Geotechnical Engineering, Sapienza Univ. of Rome, Via Eudossiana 18, 00184 Rome, Italy.
2. Research Associate, National Research Council, Institute for Geo-Engineering and Environmental Geology, c/o Faculty of Engineering, Via Eudossiana 18, 00184 Rome, Italy (corresponding author).
3. Assistant Professor, Dept. of Chemical, Mining and Environmental Engineering, Univ. of Bologna, Via Terracini 28, 40131 Bologna, Italy.