1. Postgraduate, Dept. of Civil Engineering, Shanghai Jiao Tong Univ., 800 Dongchuan Rd., Shanghai 200240, China.
2. Professor of Engineering, Research Institute of Rail Transit and Underground Space Design, Shanghai Urban Construction Design and Research Institute, 3447 Dongfang Rd., Shanghai 200125, China.
3. Professor, Dept. of Civil Engineering, Shanghai Jiao Tong Univ., 800 Dongchuan Rd., Shanghai 200240, China.
4. Assistant Professor, Dept. of Civil Engineering, Shanghai Jiao Tong Univ., 800 Dongchuan Rd., Shanghai 200240, China (corresponding author).