1. Lecturer, Dept. of Bridge Engineering, Southwest Jiaotong Univ., Chengdu 610031, China; Member, Key Laboratory of Transportation Tunnel Engineering, Ministry of Education, Chengdu 610031, China; formerly, Ph.D. Student, Dept. of Civil and Environmental Engineering, Hong Kong Polytechnic Univ., Hong Kong, China (corresponding author).
2. Chair Professor, Dept. of Civil and Environmental Engineering, Hong Kong Polytechnic Univ., Hong Kong, China.
3. Professor, Dept. of Bridge Engineering, Southwest Jiaotong Univ., Chengdu 610031, China.