1. Ph.D. Candidate, National Engineering Laboratory of Highway Maintenance Technology, Changsha Univ. of Science and Technology, Changsha 410205, China.
2. Professor, National Engineering Laboratory of Highway Maintenance Technology, Changsha Univ. of Science and Technology, Changsha 410205, China (corresponding author).
3. Professor, National Engineering Laboratory of Highway Maintenance Technology, Changsha Univ. of Science and Technology, Changsha 410205, China.
4. Lecturer, Aston Institute of Materials Research, School of Engineering and Applied Science, Aston Univ., Birmingham B4 7ET, UK.