1. Researcher, Dept. of Engineering, Roma Tre Univ., Via Vito Volterra 62, Rome 00146, Italy (corresponding author).
2. Dept. of Civil, Architectural, and Environmental Engineering, Univ. of Miami, 1251 Memorial Dr., McArthur Engineering Bldg., Coral Gables, FL 33146-0630.
3. Professor, Dept. of Engineering, Roma Tre Univ., Via Vito Volterra 62, Rome 00146, Italy.
4. Professor, Dept. of Civil, Architectural, and Environmental Engineering, Univ. of Miami, 1251 Memorial Dr., McArthur Engineering Bldg., Coral Gables, FL 33146-0630.