1. Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst, MA 01003.
2. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst, MA 01003.
3. Postdoctoral Fellow, Dept. of Earth and Environmental Engineering, Columbia Univ., New York, NY 10027.
4. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst, MA 01003.
5. Professor and Head, Dept. of Civil and Environmental Engineering, Univ. of Massachusetts, Amherst, MA 01003 (corresponding author).