1. Associate Professor, Dept. of Structural, Geotechnical, and Building Engineering, Politecnico di Torino, 10129 Turin, Italy.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Rice Univ., Houston, TX 77005 (corresponding author).
3. Professor Emeritus, Dept. of Civil, Structural, and Environmental Engineering, Univ. at Buffalo, Buffalo, NY 14260.