Three-dimensional stability analysis of plate anchors in clay

Soil anchors can be square, circular or rectangular in shape and are commonly used as foundation systems for structures requiring uplift or lateral resistance. Existing numerical analyses, however, commonly assume a condition of plane strain for numerical convenience, and the anchor is then idealised as a continuous strip. This paper applies numerical limit analysis to evaluate the effect of anchor shape on the pullout capacity of horizontal anchors in undrained clay. Estimates of the ultimate pullout load are obtained by using a newly developed three dimensional numerical procedure based on a finite element formulation of the lower bound theorem of limit analysis.