1. Assistant Professor, Dept. of Bridge Engineering, Southwest Jiaotong Univ., Chengdu 610031, China.
2. Professor, Key Laboratory of Civil Engineering Safety and Durability of the China Education Ministry, Dept. of Civil Engineering, Tsinghua Univ., Beijing 100084, China (corresponding author).
3. Ph.D. Candidate, Dept. of Civil Engineering, Tsinghua Univ., Beijing 100084, China.
4. Professor, Key Laboratory of Civil Engineering Safety and Durability of the China Education Ministry, Dept. of Civil Engineering, Tsinghua Univ., Beijing 100084, China.