1. Senior Researcher, GS Engineering and Construction, HCM City MRT CP2, Ho Chi Minh City, Vietnam.
2. Graduate Student, School of Civil Engineering, Purdue Univ., West Lafayette, IN 47907.
3. Graduate Student, School of Civil, Environmental, and Architectural Engineering, Korea Univ., Seoul 136-713, South Korea.
4. Professor, School of Civil, Environmental, and Architectural Engineering, Geosystems Laboratory, Korea Univ., Science Campus, 5-Ga, Anam-Dong, Seongbuk-Gu, Seoul, 136-713 South Korea (corresponding author).