1. Federal Highway Administration, Turner-Fairbank Highway Research Center, 6300 Georgetown Pike, McLean, VA 22101-2296.
2. Dept. of Civil Engineering, Howard Univ., 2300 6th St., NW, Washington, DC 20059.
3. Dept. of Civil Engineering, Univ. of Maryland, College Park, MD 20742.
4. Transportation Engineer, BMI-SG, 8330 Boone Blvd., Suite 400, Vienna, VA 22182.