[Ma, Wangyu] Transtec Grp, Mechanicsburg, PA 17055 USA.^[Wang, Di] Aalto Univ, Dept Civil Engn, Espoo, Finland.^[Chen, Chen] Auburn Univ, Natl Ctr Asphalt Technol, Auburn, AL USA.^[Tang, Qinrui] German Aerosp Ctr DLR, Inst Transportat Syst, Berlin, Germany.^[Gu, Fan] Changsha Univ Sci & Technol, Natl Engn Res Ctr Highway Maintenance Technol, Sch Traff & Transportat Engn, Changsha, Hunan, Peoples R China.