1. Professor, Dept. of Civil Engineering, Zhejiang Univ., Hangzhou 310027, Zhejiang, PRC.
2. Associate Professor, Centre for Infrastructure Engineering and Safety, School of Civil and Environmental Engineering, The Univ. of New South Wales, NSW, 2052, Australia.
3. Professor, Centre for Infrastructure Engineering and Safety, School of Civil and Environmental Engineering, The Univ. of New South Wales, NSW, 2052, Australia. E-mail: m.bradford@unsw.edu.au
4. Professor, Centre for Infrastructure Engineering and Safety, School of Civil and Environmental Engineering, The Univ. of New South Wales, NSW, 2052, Australia.