1. State Key Laboratory of Geomechanics and Geotechnical Engineering, Inst. of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, CN (Corresponding author), e-mail: william_bai@yeah.net; wbai@whrsm.ac.cn
2. State Key Laboratory of Geomechanics and Geotechnical Engineering, Inst. of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, CN, e-mail: lwkong@whrsm.ac.cn
3. State Key Laboratory of Geomechanics and Geotechnical Engineering, Inst. of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, CN, e-mail: agguo@whrsm.ac.cn
4. State Key Laboratory of Geomechanics and Geotechnical Engineering, Inst. of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, CN, e-mail: robin_lin@163.com