1. Assistant Professor, Dept. of Civil Engineering, Bengal Engineering and Science Univ., Shibpur, Howrah-711 103, India (corresponding author). E-mail: ambarish@civil.becs.ac.in
2. Formerly, Professor and Head, Dept. of Civil Engineering, I.I.T Kharagpur, Advisor–Consultant, Geo-Environ, D/3 Garud Heritage, Pune-411 007, India. E-mail: csubbarao2005@yahoo.com