1. Associate Professor, School of Civil Engineering, Central South Univ., Changsha 410075, China.
2. Former Ph.D. Student, Dept. of Civil and Environmental Engineering, Louisiana State Univ., Baton Rouge, LA 70803 (corresponding author).
3. Professor, Dept. of Civil and Environmental Engineering, Louisiana State Univ., Baton Rouge, LA 70803.
4. Graduate Research Assistant, School of Civil Engineering, Central South Univ., Changsha 410075, China.