1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing, P. R. China
2. School of Earth Sciences and Engineering, Nanjing University, Nanjing, P. R. China
3. School of Highway, Chang’an University, Xi’an, P. R. China
4. School of Transportation, Shandong University of Science and Technology, Qingdao, P. R. China
5. Institute of Geotechnical Engineering, School of Transportation, Southeast University, Nanjing, P. R. China