1. Lecturer, Dept. of Structural Engineering, Mansoura Univ., 60 EL-Gomhorya St., Mansoura Egypt, 35516.
2. Iovino Chair Professor, Dept. of Civil and Envir. Eng., Rensselaer Polytechnic Institute, 110 8th St, Troy, NY 12180-3590.
3. Institute Professor, Dept. of Civil and Envir. Eng., Rensselaer Polytechnic Institute, 110 8th St., Troy, NY 12180-3590.