1. Lect., Dept. of Civ. Engrg., Univ. of Durban-Westville, Durban, South Africa.
2. Prof., Dept. of Arch. and Regional Plng., Indian Inst. of Technol., Kharagpur-721 302, India.
3. Assoc. Prof., Dept. of Civ. Engrg., Indian Inst. of Technol., Kharagpur-721 302, India (corresponding author).