1. College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan, PR China;
2. Hunan Key Laboratory of Geomechanics and Engineering Safety, Xiangtan University, Xiangtan, PR China;
3. School of Civil Engineering, Central South University, Changsha, PR China;
4. CAS Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Guangzhou, PR China