1. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, 1372 Campus Delivery, Colorado State Univ., Fort Collins, CO 80523-1372.
2. Professor and Head, Dept. of Civil and Environmental Engineering, 1372 Campus Delivery, Colorado State Univ., Fort Collins, CO 80523-1372 (corresponding author).
3. Associate Professor, Dept. of Civil and Environmental Engineering, Bucknell Univ., Lewisburg, PA 17837.