1. Highway Research Division, Korea Institute of Construction Technology, (Daehwa-Dong) 283, Goyangdae-Ro, Ilsanseo-Gu, Gyeonggi-Do, Goyang-Si 411-712, Republic of Korea
2. Department of Civil Engineering, Chonbuk National University, 567 Baekje-Daero, Deokjin-Gu, Jeonbuk, Jeonju-Si 561-756, Republic of Korea
3. Department of Transportation Engineering, Hanyang University, 1271 Sa 1-Dong, Gyeonggi-Do, Ansan-Si 426-791, Republic of Korea