1. Research Staff, School of Civil, Mining and Environmental Engineering, Faculty of Engineering and Information Systems, Univ. of Wollongong, New South Wales, NSW 2522, Australia; formerly, Associate Professor, Dept. of Applied Mechanics, Faculty of Engineering and Technology, Bengal Engineering and Science Univ., Shibpur, Howrah 711103, India (corresponding author).
2. Formerly, Postgraduate Student, Dept. of Applied Mechanics, Bengal Engineering and Science Univ., Howrah 711103, India.