1. Jiangsu Expressway Company Limited, No. 6 Xianlin Avenue, Nanjing 210046, China
2. School of Technology, Tibet University, Lasa 850001, China
3. School of Transportation, Southeast University, 2 Sipailou, Nanjing 210096, China
4. Department of Civil Engineering, Toronto Metropolitan University, Toronto, ON M5B 2K3, Canada