Evaluate the bearing capacity of CFG pile by numerical method

  • N B Umravia
  • C.H. Solanki Professor, Applied Mechanics Department, Sardar Vallbhbhai National Institute of Technology, Surat
Keywords: Numerical analysis; Soft soils; CFG (Cement-Fly Ash Gravel) Pile; PLAXIS-2D; DM Deep mixing Column, Stress Distribution.

Abstract

Numerical modeling by finite element method or by finite difference method is becoming popular. The numerical or statistical model cannot predict the actual in-situ behavior of soil under loading conditions. It is the accuracy of the mathematical tool, which plays a significant role in predicting the behavior of the model and helps in an experimental model. Geotechnical engineers face many difficult challenges when design structure over soft soils. These include lateral displacement and movement, potential bearing failure, Differential settlement, local and global instability. Cement fly-Ash Grave (CFG) piles with composite foundation are widely used for ground improvement technique. It would be help to reduce the Geotechnical difficult problem of structure over soft soil.  This paper aim is to the parametric study of CFG pile using the FEM method. This numerical analysis had carried out using FEM software PLAXIS 2D. In this paper study two dimensions axisymmetric model validated by Finite element approach (FE) using with different Diameters of a pile, length variation, strength of pile, Cohesive of Soft Soil. discussed were on based of FE models results; the pile stress under prescribed settlement  as well soil stress distribution under load and pile-soil stress concentration ratio of the CFG Piles for evaluate bearing capacity under the soft soil. The results indicate that the soil pressure distribution and stress on the pile is relatively to compare the load-deformation behavior with the model tests.

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Published
2018-10-05