1. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Virginia Tech, 200 Patton Hall, Blacksburg, VA 24061 (corresponding author).
2. Research Assistant Professor, Dept. of Civil and Environmental Engineering, Virginia Tech, 200 Patton Hall, Blacksburg, VA 24061.
3. Professor, Dept. of Civil and Environmental Engineering, Virginia Tech, 200 Patton Hall, Blacksburg, VA 24061.