1. Assitant Professor, Institute of Geotechnical Engineering, Hunan Univ., Changsha 410082, People’s Republic of China (corresponding author).
2. Ph.D. Candidate, Institute of Geotechnical Engineering, Hunan Univ., Changsha 410082, People’s Republic of China.
3. Professor, Institute of Geotechnical Engineering, Hunan Univ., Changsha 410082, People’s Republic of China.
4. Professor, College of Civil Engineering, Hunan Univ., Changsha 410082, People’s Republic of China.