1. Professor, School of Civil Engineering and Mechanics, Huazhong Univ. of Science and Technology (HUST), 1037 Luoyu Rd., Wuhan 430074, P.R. China.
2. Ph.D. Candidate, School of Civil Engineering and Mechanics, Huazhong Univ. of Science and Technology (HUST), 1037 Luoyu Rd., Wuhan 430074, P.R. China (corresponding author).
3. Associate Professor, Institute of Systems Engineering, Huazhong Univ. of Science and Technology (HUST), 1037 Luoyu Rd., Wuhan 430074, P.R. China.