1. Professor, Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji Univ., 1239 Siping Rd., Shanghai 200092, P.R. China.
2. Ph.D. Candidate, Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education, Tongji Univ., 1239 Siping Rd., Shanghai 200092, P.R. China (corresponding author).
3. Senior Engineer, Shanghai CAAC New Era Airport Design and Research Institute, 99 Konggang No. 1 Rd., Shanghai 200335, P.R. China.
4. Engineer, Shanghai CAAC New Era Airport Design and Research Institute, 99 Konggang No. 1 Rd., Shanghai 200335, P.R. China.