1. Assistant Professor, Dept. of Civil Engineering, Technological Univ. of Panama, PTY #12450, P.O. Box 25207, Miami, FL 33102 (corresponding author). E-mail: ramiro.vargas@utp.ac.pa
2. Professor and MCEER Director, Dept. of Civil, Structural and Environmental Engineering, State Univ. of New York at Buffalo, 130 Ketter Hall, Buffalo, NY 14260. E-mail: bruneau@buffalo.edu