1. Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, 3140 Newmark Civil Engineering Bldg, 205 N. Mathews, Urbana, IL 61801; Dept. of Architecture, Faculty of Fine-Arts, Univ. of Helwan, 4 Mohamed Thakeb St., Zamalek, Cairo, Egypt.
2. Dept. of Civil and Environmental Engineering, Univ. of Illinois at Urbana-Champaign, 3112 Newmark Civil Engineering Bldg, 205 N. Mathews, Urbana, IL 61801 (corresponding author).