1. Senior Lecturer, School of Engineering and Built Environment, Griffith Univ., 170 Kessels Rd., Nathan, QLD 4111, Australia (corresponding author).
2. Geotechnical Engineer, Keller (M) Sdn Bhd, B5-10, Block B, Plaza Dwitasik, Bandar Sri Permaisuri, Off Jalan Tasik Permaisuri 1, Kuala Lumpur 56000, Malaysia; formerly, Research Scholar, Research Centre for Sustainable Technologies, Swinburne Univ. of Technology Sarawak Campus, Kuching, Sarawak 93350, Malaysia.
3. Professor, National Univ. of Singapore, 21 Lower Kent Ridge Rd., Singapore 119077, Singapore.