1. Ph.D. Candidate, Key Laboratory of Highway Engineering in Special Region of Ministry of Education, Chang’an Univ., Xi’an 710064, Shaanxi, China.
2. Assistant Engineer, Road Material Centre, Shandong Transportation Institute, Jinan 250031, Shandong, China.
3. Assistant Engineer, Road Material Centre, Shandong Transportation Institute, Jinan 250031, Shandong, China (corresponding author).