1. Research Assistant, The Asphalt Pavement Research Group, Dept. of Civil and Environmental Engineering, The Univ. of Wisconsin–Madison, 2210 Engineering Hall, 1415 Engineering Dr., Madison, WI 53706 (corresponding author).
2. Professor, The Asphalt Pavement Research Group, Dept. of Civil and Environmental Engineering, The Univ. of Wisconsin–Madison, 2210 Engineering Hall, 1415 Engineering Dr., Madison, WI 53706.
3. The Federal Highway Administration, HTA-21, Room 6319, 400 Seventh St. SW, Washington, D.C. 20590.