1. Postdoctoral Researcher, Alabama Transportation Institute, Univ. of Alabama, P.O. Box 870288, Tuscaloosa, AL 35487-0205 (corresponding author).
2. Research Engineer, Dept. of Civil Construction and Environmental Engineering, Univ. of Alabama, P.O. Box 870288, Tuscaloosa, AL 35487-0205.
3. Assistant Professor, Dept. of Civil Construction and Environmental Engineering, Univ. of Alabama, P.O. Box 870288, Tuscaloosa, AL 35487-0205.
4. Professor, Dept. of Civil Construction and Environmental Engineering, Univ. of Alabama, P.O. Box 870288, Tuscaloosa, AL 35487-0205.