1. Assistant Professor, Dept. of Civil and Environmental Engineering, Washington State Univ., Spokane St., Sloan Hall 41, Pullman, WA 99164-2910 (corresponding author).
2. Research Assistant, Dept. of Civil and Environmental Engineering, Washington State Univ., Spokane St., Sloan Hall 37, Pullman, WA 99164-2910.
3. Assistant Professor, School of Civil Engineering, Shandong Univ., 17922 Jingshi Rd., Jinan 250061, China.