1. Associate Professor, School of Civil Engineering, Sichuan Univ. of Science and Engineering, Zigong 643000, China (corresponding author).
2. Associate Professor, School of Civil Engineering, Sichuan Univ. of Science and Engineering, Zigong 643000, China; National and Local Joint Engineering Research Center of Shale Gas Exploration and Development, Chongqing Institute of Geology and Mineral Resources, Chongqing 401120, China.
3. Associate Professor, School of Civil Engineering, Sichuan Univ. of Science and Engineering, Zigong 643000, China; State Key Laboratory of Geohazards Prevention and Geoenvironment Protection, Chengdu Univ. of Technology, Chengdu 610059, China.