1. Assoc. Prof., Dept. of Civ. Engrg., Nat. Univ. of Singapore, 10 Kent Ridge Crescent, Singapore 0511
2. Res. Student, Dept. of Civ. Engrg., Nat. Univ. of Singapore, 10 Kent Ridge Crescent, Singapore 0511
3. Sr. Lect., Dept. of Civ. Engrg., Nat. Univ. of Singapore, 10 Kent Ridge Crescent, Singapore 0511