1. Associate Professor, Dept. of Civil and Environmental Engineering, 301 DuPont Hall, Univ. of Delaware, Newark, DE 19716.
2. Graduate Student, Dept. of Civil and Environmental Engineering, 301 DuPont Hall, Univ. of Delaware, Newark, DE 19716.
3. Assistant Professor, Dept. of Civil and Environmental Engineering, 301 DuPont Hall, Univ. of Delaware, Newark, DE 19716 (corresponding author).