Effect of Keying-Induced Soil Remolding on the Ultimate Pull-Out Capacity and Embedment Loss of Strip Anchors in Clay

Abstract

In this paper, the keying of strip anchors in clay has been studied by employing a large deformation finite-element methodology coupled with a soil constitutive model that takes strain rate and soil remolding into considerations. The influences of soil strength degradation during keying on the loss of embedment and undrained pull-out resistance of anchors have been investigated by varying several factors, such as soil sensitivity, initial embedment depth, loading eccentricity, and shear strength heterogeneity. The methodology is validated with results from experimental and theoretical studies available in the literature. A generalized approach is developed to assess the maximum embedment loss and ultimate pull-out capacity. A combined dimensionless parameter as a function of the initial anchor depth and normalized equivalent soil strength is introduced for the prediction of maximum embedment loss. Ultimate pull-out factors normalized by an equivalent shear strength of soil are presented as a function of the initial embedment for different soil-strength heterogeneity and anchor eccentricity. Simplified expressions are provided for adoption in the routine design practice.