1. Professor, Geotechnical Research Institute, College of Civil and Transportation Engineering, Hohai Univ., 1 Xi Kang Rd., Nanjing 210098, China (corresponding author).
2. Ph.D. Candidate, Geotechnical Research Institute, College of Civil and Transportation Engineering, Hohai Univ., 1 Xi Kang Rd., Nanjing 210098, China.