Evaluation of Key Parameters Affecting the Bearing Capacity of Helical Piles

This experimental study examined the axial performance of helical piles subjected to compressive and tensile loads, with a particular focus on the effects of helix spacing, number of helices, soil compaction, and loading type. Employing a large-scale frustum-confining vessel (AUT-FCV) to accurately simulate in-situ stress conditions, the behavior of single- and double-helix piles was analyzed in medium- and low-density sandy soils. The findings revealed that soil compaction significantly enhanced pile performance, with medium-dense soils markedly increasing both the compressive and tensile capacities. Optimal performance was observed in double-helix piles with a helix spacing of ۱.۵ times the diameter, which demonstrated an improved load-bearing capacity and reduced displacement. Notably, in well-compacted soils, the tensile bearing capacity approached or equaled the compressive capacity, underscoring the suitability of helical piles for uplift-resisting applications in such conditions. These results contribute to the advancement of more effective design methodologies for helical pile foundations in sandy soils, particularly in coastal and urban geotechnical contexts.

کلیدواژه ها:

Helical pile ، Bearing capacity ، Soil density ، Compressive and Tensile loading ، Physical modeling