1. Research Associate, Dept. of Civil and Environmental Engineering, The Hong Kong Univ. of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China (corresponding author).
2. Senior Lecturer, Dept. of Civil and Natural Resources Engineering, The Univ. of Canterbury, Private Bag 4800 Christchurch, New Zealand.
3. Professor, Dept. of Civil and Environmental Engineering, The Hong Kong Univ. of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.