1. Graduate Student, School of Civil and Environmental Engineering, Hollister Hall, Cornell Univ., Ithaca, NY 14853-3501.
2. Assistant Professor, School of Civil and Environmental Engineering, Hollister Hall, Cornell Univ., Ithaca, NY 14853-3501 (corresponding author).
3. Department Head and A.P. and Florence Wiley Chair Professor, Zachry Dept. of Civil Engineering, Texas A&M Univ., 3136 TAMU, College Station, TX 77843-3136.formerly, Professor, Dept. of Civil Engineering, Apperson Hall, Oregon State Univ.
4. Professor, School of Civil and Environmental Engineering, Hollister Hall, Cornell Univ., Ithaca, NY 14853-3501.