1. Associate Professor, School of Civil, Mining and Environmental Engineering, Univ. of Wollongong, New South Wales 2522, Australia (corresponding author).
2. Ph.D. Student, School of Civil, Mining and Environmental Engineering, Univ. of Wollongong, New South Wales 2522, Australia.
3. ME Research Student, School of Civil, Mining and Environmental Engineering, Univ. of Wollongong, New South Wales 2522, Australia.