1. Associate Professor, Dept. of Civil and Architectural Engineering, Sultan Qaboos Univ., P.O. Box 33, Al-Khod PC 123, Muscat, Sultanate of Oman (corresponding author).
2. Associate Professor, Dept. of Civil and Architectural Engineering, Sultan Qaboos Univ., P.O. Box 33, Al-Khod PC 123, Muscat, Sultanate of Oman.