Load Capacity of Helical Piles with Different Geometrical Aspects in Sandy and Clayey Soils: A Numerical Study

Abstract

In recent years, using helical piles as deep foundations for different types of structures has been increased considerably. In this paper, by using finite element software (ABAQUS), the compressive and tensile load capacities of helical piles screwed in sandy and clayey soils have been studied numerically and corresponding load-displacement curves are presented. For this purpose, different geometrical aspects of the helical pile element (including the pile length, the main shaft diameter, the helix diameter and the internal helix spacing) have been taken into account for different soil properties conditions. In modeling efforts, a disturbed zone around the pile element is also considered for better catching the effect of the soil disturbance during pile installation procedure.

Based on the obtained results, it is observed that for both types of the studied soils, increasing the helix diameter leads to an increase in load capacities. In addition, it is observed that by increasing the internal helix spacing up to three times of the helix diameter, the ultimate load capacities were increased and then remained almost unchanged. Similar trend was obtained from parametric study on the main shaft diameter. However, increasing the pile length was shown to have consistent increasing effect on the ultimate load capacities.

In this paper, to verify the obtained results, some experimental records are also considered and compared statistically with corresponding load capacities from numerical simulations. Comparisons show very good agreement between the numerical results, the experimental records and analytical solutions.