1. School of Civil and Architectural Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si 16419, Republic of Korea
2. Department of Civil & Environmental Engineering, Dankook University, 126 Jukjeon-dong, Suji-gu, Yongin-si 448-701, Republic of Korea
3. Department of Civil Engineering, Semyung University, 579 Sinwoul-dong, Jecheon-si, Chungbuk 390-711, Republic of Korea