1. Assistant Professor, Division of Construction Engineering and Management, School of Civil Engineering, Purdue Univ., 550 Stadium Mall Drive, West Lafayette, IN 47907 (corresponding author).
2. Associate Professor, Dept. of Civil and Construction Engineering, Western Michigan Univ., Kalamazoo, MI 49008-5316.
3. Highway Research Engineer, Turner-Fairbank Highway Research Center, FHWA, U.S. DOT, 6300 Georgetown Pike, HRDO-20, McLean, VA 22101.