1. Professor, Dept. of Civil and Structural Engineering, Hong Kong Polytechnic Univ., Hung Hom, Kowloon, Hong Kong, China.
2. Ph.D. student, Dept. of Civil and Structural Engineering, Hong Kong Polytechnic Univ., Hung Hom, Kowloon, Hong Kong, China (corresponding author).
3. Assistant Professor, Faculty of Science and Technology, Univ. of Macau, China.