Numerical analysis of short pile under oblique pull out in sandy soil

Document Type : Research Article


M. Sc., Yazd University


In many cases, piles have been used to counteract the pull-out force for engineering purposes. In this research, the behavior of short piles with a slenderness ratio (λ = L / B) less than 10, at oblique pull-out loading with different (inclination) angles in sandy soils was investigated using nonlinear models of Flac3D software. The Mohr-Coulomb behavioral model was selected for soil and the analyzes were performed in large strain conditions. In this study, a reinforced concrete pile with a cross-section of 1.2x1.2 m2 in dense sandy soil and buried depth of 10 m was considered. According to the results of numerical analysis, the relations provided by Das and Seeley (1975) were challenged. The load-displacement curves were presented with different uplift load inclination angles. These curves showed that the uplift capacity of the pile increases with the addition of the horizontal component of force. For instance, the load inclination angle of 60o, the uplift capacity of the pile was increased by 12% higher than the net uplift state. Furthermore, vertical displacement and pile deflection versus load application angle was plotted based on the numerical results. Also, a significant relationship has been found between the coefficient β introduced by Ismael and Al-Sanad (1994), and the slenderness ratio (λ) according to other laboratory studies and numerical results of this study.


Main Subjects

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