1. Institute of Structural Engineering, Zhejiang Univ., 610 Anzhong Bldg., 866 Yuhangtang Rd., Hangzhou 310058, China.
2. Assistant Professor, Dept. of Civil and Environment Engineering, Hong Kong Polytechnic Univ., Rm. ZS948 Bldg. Z, Hung Hom, Kowloon 999077, Hong Kong.
3. Professor, Institute of Structural Engineering, Zhejiang Univ., 607 Anzhong Bldg., 866 Yuhangtang Rd., Hangzhou 310058, China (corresponding author).