1. Senior Researcher, National Research Council, Via Madonna Alta 126, 06128 Perugia, Italy.
2. Full Professor, Dept. of Civil and Environmental Engineering, Univ. of Perugia, via G. Duranti 93, 06125 Perugia, Italy.
3. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Perugia, via G. Duranti 93, 06125 Perugia, Italy (corresponding author).
4. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Perugia, via G. Duranti 93, 06125 Perugia, Italy.
5. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of Perugia, via G. Duranti 93, 06125 Perugia, Italy.