1. School of Transportation Science and Engineering, Harbin Institute of Technology, Nangang District, Harbin, PR China; Institute of Highway Engineering, RWTH Aachen Univ., Aachen, Germany
2. School of Transportation Science and Engineering, Harbin Institute of Technology, Nangang District, Harbin, PR China
3. School of Transportation Science and Engineering, Harbin Institute of Technology, Nangang District, Harbin, PR China.