Computers and Concrete

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Bearing capacity at the pile tip embedded in rock depending on the shape factor and the flow

  • Ana S. Alencar (ETSI Caminos, C. y P., Universidad Politecnica de Madrid) ;
  • Ruben A. Galindo (ETSI Caminos, C. y P., Universidad Politecnica de Madrid) ;
  • Miguel A. Millan (ETS Arquitectura. Universidad Politecnica de Madrid)
  • Received : 2022.12.10
  • Accepted : 2023.02.24
  • Published : 2023.05.25
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Abstract

This is a research analyses on the bearing capacity at a pile tip embedded in rock. The aim is to propose a shape coefficient for an analytical solution and to investigate the influence of the plastic flow law on the problem. For this purpose, the finite difference method is used to analyze the bearing capacity of various types and states of rock masses, assuming the Hoek & Brown failure criterion, by considering both plane strain and an axisymmetric model. Different geometrical configurations were adopted for this analysis. First, the axisymmetric numerical results were compared with those obtained from the plane strain analytical solution. Then the pile shape influence on the bearing capacity was studied. A shape factor is now proposed. Furthermore, an evaluation was done on the influence of the plastic flow law on the pile tip bearing capacity. Associative flow and non-associative flow with null dilatancy were considered, resulting in a proposed correlation. A total of 324 cases were simulated, performing a sensitivity analysis on the results and using the graphic output of vertical displacement and maximum principal stress to understand how the failure mechanism occurs in the numerical model.

Keywords

References

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