1. Associate Professor, Civil Engineering Dept., King Fahd Univ. of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
2. Assistant Professor, Civil Engineering Dept., King Fahd Univ. of Petroleum and Minerals, Dhahran 31261, Saudi Arabia. E-mail: asi@kfupm.edu.sa; presently, Assistant Professor, Hashemite Univ., P.O. Box 960515, Amman 11196, Jordan.
3. Professor, Civil Engineering Dept., King Fahd Univ. of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
4. Research Engineer, Research Institute, King Fahd Univ. of Petroleum and Minerals, Dhahran 31261, Saudi Arabia; presently, Project Engineer, Gulf Engineering House, P.O. Box 27108, Riyadh 11417, Saudi Arabia.