1. Postdoctoral Researcher, School of Civil Engineering and Mechanics, Huazhong Univ. of Science and Technology, Wuhan, Hubei 430074, P.R. China (corresponding author).
2. Professor, School of Civil Engineering and Mechanics, Huazhong Univ. of Science and Technology, Wuhan, Hubei 430074, P.R. China.
3. Professor, School of Civil Engineering, Tongji Univ., Shanghai 200092, P.R. China.