1. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Ann Arbor, MI 48109.
2. Assistant Professor, Dept. of Civil and Environmental Engineering, Rutgers Univ., 500 Bartholomew Rd., Piscataway, NJ 08854.
3. Professor, Dept. of Civil and Environmental Engineering, Univ. of Michigan, 2350 Hayward St., Ann Arbor, MI 48109 (corresponding author).