1. Postdoctoral Research Fellow, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843.
2. Assistant Professor, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843.
3. Professor, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843; and Mechanical Engineering Program, Texas A&M Univ. at Qatar, Doha, Qatar (corresponding author).
4. Regents Professor, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843.