1. School of Civil Engineering, Central South Univ. of Forestry and Technology, Changsha, Hunan 410004, China.
2. Professorate Senior Engineer, State Key Laboratory of Shield Machine and Boring Technology, Zhengzhou, Henan 450001, China.
3. Professor, School of Civil Engineering, Central South Univ., Changsha, Hunan 410075, China.
4. Associate Professor, School of Civil Engineering, Central South Univ., Changsha, Hunan 410075, China.
5. Ph.D. Candidate, School of Civil Engineering, Central South Univ., Changsha, Hunan 410075, China (corresponding author).