Numerical Modelling of the Uplift Behaviour of Circular Plate Anchors in Sand

Abstract

Axisymmetric finite element analyses of the uplift behaviour of circular anchors in sand using the ANSYS package are reported. The non-linear behaviour of soil was incorporated in the analysis by using the MISO (Multi-linear Isotropic Hardening Material) model. The influence of soil type, friction angle and depth of anchor embedment on uplift response was investigated. The load-displacement relationship obtained from the non-linear finite element analyses compares well with published results. The ultimate pullout load increased with embedment ratio and soil friction angle. Critical embedment ratios of 5, 6.5 and 7.5 were obtained for anchors in sand with friction angles consistent with loose, medium-dense and dense packings. Computed breakout factors compared fairly well with predictions from various theories, Meyerhof and Adams theory providing best overall agreement, particularly for shallow anchors in loose sand and for deeper ones in medium-dense and dense sand. Comparisons with previously reported experimental work were also reasonable.