1. Geotechnical Engineer, Golder Associates (Hong Kong) Limited, 17/F, No. 88 Gloucester Rd., Wan Chai, Hong Kong.
2. Lecturer, Univ. College Cork, Civil and Environmental Engineering Bldg., College Rd., Cork, Republic of Ireland (corresponding author).
3. Professor, Dept. of Engineering, Univ. of Cambridge, Trumpington St., Cambridge CB2 1PZ, U.K.