1. Ph.D. Student, School of Highway, Chang’an Univ., No. 126, Middle Section of South Second Ring Rd., Xi’an, Shaanxi 710064, China.
2. Engineer, Shandong High-Speed Group Co., Ltd., No. 8, Long’ao North Rd., Jinan, Shandong 250098, China.
3. Professor, School of Highway, Chang’an Univ., No. 126, Middle Section of South Second Ring Rd., Xi’an, Shaanxi 710064, China (corresponding author).