1. Department of Civil and Environmental Engineering, Sejong University, No. 209, Neungdong-ro, Gwangjin-gu, Seoul 143-747, Republic of Korea
2. School of Urban and Environmental Engineering, UNIST, 50 UNIST-gil, Ulju-gun, Ulsan 689-798, Republic of Korea
3. College of Engineering, Mathematics & Physical Sciences, University of Exeter, Harrison Building, North Park Road, Exeter EX4 4QF, UK
4. Korea Expressway Corporation Research Institute, No. 208-96, Dongbu-daero 922 beon-gil, Dongtan-myeon, Hwaseong-si, Gyeonggi-do, Republic of Korea