1. Professor and Chairman, Dept. of Civil and Environmental Engineering, American Univ. of Beirut, P.O. Box 11-0236, Riad El Solh 1107 2020, Beirut, Lebanon.
2. Graduate Student, Dept. of Civil Engineering, Univ. of Waterloo, Waterloo ON, Canada.
3. Associate Professor, Dept. of Civil Engineering, Univ. of Waterloo, Waterloo ON, Canada.