End Bearing Capacity of Drilled Shafts in Sand: A Numerical Approach

  • M. M. Ahmadi
  • M. Khabbazian
Original Paper


In this paper, a modeling procedure is carried out to numerically analyze the end bearing capacity of drilled shafts in sand. The Mohr–Coulomb elastic plastic constitutive law with stress dependent elastic parameters is used for all numerical analyses performed in this study. The numerical results are compared with the available experimental equations. It is seen that numerical results are in good agreement with experimental equations. The variation of the end bearing capacity of drilled shafts versus embedment depth is also studied. Numerical results show that with increase in pile embedment depth, the end bearing capacity increases. However, the rate of increase becomes smaller as the pile embedment depth increases. Also, numerical analyses show that, for equal settlement, the end bearing decreases with increase in the pile diameter. Finally, a sensitivity analysis is performed to obtain the separate effect of each sand parameter on the end bearing capacity of drilled shafts, and the parameters that are most influential are identified.


Drilled shaft Embedment depth End bearing capacity Numerical modeling Sand 



Pile diameter




Relative density


Elasticity modulus


Shear modulus


Bulk modulus


Bulk stiffness number


Shear stiffness number


Coefficient of lateral earth pressure at rest


Embedment depth of drilled shaft


Stress exponent


Stress exponent


The average standard penetration resistance in blows per foot near the pile tip


Atmospheric pressure


End bearing capacity


Pile tip displacement


Friction angle


Critical angle of shearing resistance of sand


Sand density


Poisson ratio


Mean effective stress


Dilation angle


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Department of Civil EngineeringSharif University of TechnologyTehranIran

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