Three-dimensional finite element analysis for uplifting independent helix plate anchor in uniform clay

Abstract

Three-dimensional finite element analysis offers a more realistic representation of the geometry of the helix plate anchor. For the helical anchor with a single helix plate or multiple helix plates whose spacing distance is large between each plate, each helix plate behaves independently during uplifting. Although numerous studies have estimated the uplift capacity factor of independent circular plate anchors in uniform clay, rare research comprehensively considers the effects of helix pitch, anchor shaft, and soil rigidity on estimating the uplift capacity factor for independent helix plate anchors. In this paper, three-dimensional finite element analyses were conducted to investigate the impacts of helix pitch, anchor shaft, and soil rigidity on estimating the uplift capacity factor of independent helix plate anchors with shafts in uniform clay. Analysis results demonstrated that the increasing helix pitch and anchor shaft diameter could significantly decrease the uplift capacity factor. The change in the soil rigidity also influenced uplift capacity factor estimation. Therefore, determining the uplift capacity factor should comprehensively account for the effects of embedment depth, helix pitch, anchor shaft, soil rigidity, and overburden pressure. In this study, a procedure was suggested for creating design guidelines to estimate uplift capacity factors for independent helix plate anchors.