1. Associate Professor, Dept. of Civil Engineering and Architecture, Univ. of Catania, Via Santa Sofia 64, 95123 Catania, Italy (corresponding author).
2. Formerly, Master Student, Dept. of Civil Engineering and Architecture, Univ. of Catania, Via Santa Sofia 64, 95123 Catania, Italy.
3. Full Professor, Dept. of Civil Engineering and Architecture, Univ. of Catania, Via Santa Sofia 64, 95123 Catania, Italy.