(1. School of Resources and Safety Engineering, Central South University, Changsha 410083, China; 2. College of Civil Engineering, Hunan University, Changsha 410082, China; 3. School of Bridge and Structure Engineering, Changsha University of Science and Technology, Changsha 410076, China; 4. Institute of Geotechnical Engineering, Xi’an University of Technology, Xi’an 710048, China)