1. College of Traffic & Transportation, Chongqing Jiaotong University, Chongqing 400074, China
2. School of Traffic & Transportation Engineering, Changsha University of Science & Technology, Changsha 410114, China
3. College of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing 400074, China
4. College of Transportation, Jilin University, Changchun 130022, China