Performance Evaluation of PVD-Reinforced Soft Soil with Surcharge and Vacuum Preloading
- 162 Downloads
Preloading method has been a widely used alternative to improve soft soil in coastal areas in China. In this paper, a field test of PVD-reinforced soft soil with surcharge preloading and vacuum preloading was introduced. Based on the field test, three-dimensional finite-element analyses were conducted to evaluate the performance of reinforced soft soil. The subsoils were simulated as linearly elastic–perfectly plastic materials with Mohr–Coulomb failure criteria. The PVDs were modeled individually as solid elements with the cross section of real PVD. The computed settlements, layered settlements, lateral displacements and excess pore water pressure were compared with the field data. The results show that the differential settlement on the ground can be minimized in the vacuum preloading. However, the environmental influence area of vacuum preloading was greater than that of surcharge preloading outside the reinforced area. The influence depth of vacuum preloading under PVD base was time dependent. And the cut-off wall had a significant effect on mitigating vacuum loss at the boundary.
KeywordsSoft soil Vacuum preloading Surcharge preloading Pore water pressure Finite element analysis
The authors appreciate the financial support provided by the National Natural Science Foundation of China (NSFC; Nos. 41272294 and 51508408) for this work. And the corresponding author is obliged to the Pujiang Talents Scheme (No. 15PJ1408800) for the continuous support for his research.
- 3.Kim TH, You SH (2015) Settlement analysis considering sand mat induced initial settlement in soft ground improved by PBD. Int J Civ Eng13(2B):146–152Google Scholar
- 4.Kjellmann W (1952) Consolidation of clay soil by means of atmospheric pressure. In: Proceedings on soil stabilization conference, Boston, USA, pp 258–263Google Scholar
- 5.Indraratna B (2010) Recent advances in the application of vertical drains and vacuum preloading in soft soil stabilization. Austr Geomech J45(2):1–44Google Scholar
- 12.Hibbitt D, Karlsson B, Sorensen P (2006) ABAQUS/standard user’s manual. HKS Inc., DallasGoogle Scholar
- 13.Holtz RD, Lancellotta R, Jamiolkowski M, Pedroni S (1991) Laboratory testing of prefabricated ‘wick’ drains. In: Proceedings of Geo-Coast’91, Yokohama, Japan, pp 311–316Google Scholar
- 17.Chen PS, Fang YG, Mo HH, Zhang GX, Dong ZL (2009) Analysis of 3D FEM for soft foundation improved by vacuum preloading. Chin J Geotech Eng 31(4):564–570(Chinese) Google Scholar
- 18.Dong ZL, Chen PS, Mo HH, Zhang GX (2008) Comparison of numerical simulation with finite element method for vacuum preloading. Chin J Rock Mech Eng27(11):2347–2353(Chinese) Google Scholar
- 21.Li JS, Sun J (1999) One dimension consolidate-creep problem of Shanghai silt clay. J Tongji Univ27(4):389–392(Chinese) Google Scholar