1. Professor, Institute of Geotechnical Engineering, Nanjing Tech Univ., Nanjing 210009, China (corresponding author).
2. Ph.D. Student, Institute of Geotechnical Engineering, Nanjing Tech Univ., Nanjing 210009, China.
3. Associate Professor, Institute of Geotechnical Engineering, Nanjing Tech Univ., Nanjing 210009, China.
4. Glenn Professor Emeritus, Glenn Dept. of Civil Engineering, Clemson Univ., Clemson, SC 29634.