1. Architectural Construction Team, Samsung Heavy Industries Co, Ltd, 1321-30 Seocho-Dong, Seocho-Gu, Seoul 137-857, Korea.
2. Construction and Economy Research Institute of Korea, 71-2 Nonhyun-dong, Kangnam-gu, Seoul 135-701, Korea.
3. Dept. of Civil Engineering, Oklahoma State University, 316 Engineering, Stillwater, OK 74078, USA.
4. School of Civil, Environmental and Architectural Engineering, Korea University, 5Ga, Anam-Dong, Sungbuk-Gu, Seoul 136-701, Korea.