1. Assistant Professor, Dept. of Civil and Structural Engineering, Hong Kong Polytechnic Univ., Hong Kong, China. E-mail: cemlu@polyu.edu.hk
2. Associate Professor, Dept. of Land Surveying and Geoinfomatics, Hong Kong Polytechnic Univ., Hong Kong, China.
3. Research Assistant, Dept. of Civil and Structural Engineering, Hong Kong Polytechnic Univ., Hong Kong, China.