1. Ph.D., Researcher, Korea Institute of Construction Technology, 283, Goyangdae-Ro Ilsan-Gu, Goyang-Si, Gyeonggi-Do, 411-712 KR, e-mail: truepath@kict.re.kr.
2. Post-doctoral Researcher, Dept. of Regional Infrastructures Engineering, Kangwon National Univ., Chuncheon, 200-701 KR, e-mail: sungun2001@hanmail.net.
3. Professor, Dept. of Regional Infrastructures Engineering, Kangwon National Univ., Chuncheon, 200-701 KR (Corresponding author), e-mail: asphaltech@hanmail.net.