1. Graduate Student, Glenn Dept. of Civil Engineering, Clemson Univ., 123 Lowry Hall, Clemson, SC 29634-0911.
2. Associate Professor, Glenn Dept. of Civil Engineering, Clemson Univ., 110 Lowry Hall, Clemson, SC 29634-0911 (corresponding author).
3. Professor, Glenn Dept. of Civil Engineering, Clemson Univ., 218 Lowry Hall, Clemson, SC 29634-0911.
4. Associate Professor, Dept. Civil and Environmental Engineering, Univ. of Texas at San Antonio, San Antonio, TX 78249-3209.