1. Professor, Dept. of Bridge Engineering, Hunan Univ., Changsha, Hunan, China.
2. Ph.D. Candidate, Dept. of Bridge Engineering, Hunan Univ., Changsha, Hunan, China (corresponding author).
3. Professor, College of Civil Engineering, Hunan Univ., Changsha, Hunan, China.
4. Ph.D. Candidate, Dept. of Bridge Engineering, Hunan Univ., Changsha, Hunan, China.