1. Ph.D. Student, Dept. of Civil, Construction, and Environmental Engineering, Colorado State Univ., Fort Collins, CO 80521.
2. George T. Abell Distinguished Professor in Infrastructure, Dept. of Civil, Construction, and Environmental Engineering, Colorado State Univ., Fort Collins, CO 80523-1372 (corresponding author).
3. Associate Professor, Dept. of Civil and Environmental Engineering, Michigan Technological Univ., Houghton, MI 49931.