1. Professor, School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea Univ., Seoul 136-713, Korea. E-mail: envchul@korea.ac.kr
2. Ph.D. Candidate, School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea Univ., Seoul 136-713, Korea (corresponding author). E-mail: kjm1868@nate.com
3. Research Assistant Professor, School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea Univ., Seoul 136-713, Korea. E-mail: civileng01@korea.ac.kr
4. Research Associate, School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea Univ., Seoul 136-713, Korea. E-mail: bbanz2@hanmail.net