1. Senior Geotechnical Engineer, SMEC Australia Pty. Ltd., 60 Leichhardt St., Spring Hill, QLD 4000, Australia; formerly, Research Fellow, Univ. of Southampton, Southampton SO17 1BJ, U.K. (corresponding author).
2. Professor of Geotechnical Engineering, School of Civil Engineering and the Environment, Univ. of Southampton, Highfield, Southampton, SO17 1BJ, U.K.
3. Senior Research Fellow, School of Civil Engineering and the Environment, Univ. of Southampton, Highfield, Southampton SO17 1BJ, U.K.,