1. Associate Professor, School of Civil, Mining and Environmental Engineering, Univ. of Wollongong, Wollongong NSW 2522, Australia (corresponding author).
2. Lecturer, Dept. of Civil Engineering, Univ. of Udayana, Bali 80361, Indonesia; presently, Ph.D. Scholar at the School of Civil, Mining and Environmental Engineering, Univ. of Wollongong, Wollongong NSW 2522, Australia.