1. Doctoral Student, School of Civil Engineering and Architecture, Changsha Univ. of Science and Technology, No. 960 Wanjiali Rd., Changsha, Hunan 410114, China; Doctoral Student, LEM3 UMR CNRS 7239, Univ. de Lorraine, Ile du Saulcy 57045 Metz Cedex 01, France.
2. Professor, School of Civil Engineering and Architecture, Changsha Univ. of Science and Technology, No. 960 Wanjiali Rd., Changsha, Hunan 410114, China (corresponding author).
3. Senior Engineer, Tianjin Transportation Research Institute, No. 25 Dongli Rd., Tianjin 300074, China.
4. Doctoral Student, School of Civil Engineering and Architecture, Changsha Univ. of Science and Technology, No. 960 Wanjiali Rd., Changsha, Hunan 410114, China.
5. Assistant Professor, School of Civil Engineering and Environmental Science, Univ. of Oklahoma, 202 W. Boyd St., Norman, OK 73019.
6. Professor, School of Civil Engineering and Architecture, Changsha Univ. of Science and Technology, No. 960 Wanjiali Rd., Changsha, Hunan 410114, China.