1. Virginia Center for Transportation Innovation and Research, Virginia Dept. of Transportation, 530 Edgemont Rd., Charlottesville, VA 22903.
2. Civil and Environmental Engineering, 351 McCormick Rd., Thornton Hall, Univ. of Virginia, Charlottesville, VA 22904.
3. Civil and Environmental Engineering, 351 McCormick Rd., Thornton Hall, Univ. of Virginia, Charlottesville, VA 22904 (corresponding author).