1. Master Student, Dept. of Civil Engineering, Tsinghua Univ., Beijing 100084, China.
2. Associate Professor, Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry, Dept. of Civil Engineering, Tsinghua Univ., Beijing 100084, China (corresponding author).
3. Professor, State Key Laboratory of Road Engineering Safety and Health in Cold and High-Altitude Regions, CCCC First Highway Consultants Co. Ltd., Xi’an 710075, China.