1. Structural Engineer, Jacobs Engineering Group, 1100 N. Glebe Rd., Arlington, VA 22201.
2. Assistant Professor, Dept. of Civil and Environmental Engineering, Auburn Univ., 238 Harbert Engineering Center, Auburn, AL 36849 (corresponding author).
3. Principal Research Scientist, Virginia Transportation Research Council, 530 Edgemont Rd., Charlottesville, VA 22903.