1. Graduate Student, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843 (corresponding author).
2. Professor, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843.
3. Geotechnical Engineer, Manager, Samsung C&T Corporation, Seoul 137857, Korea.
4. Graduate Student, Zachry Dept. of Civil Engineering, Texas A&M Univ., College Station, TX 77843.