Numerical study on the pull-out behaviour of planar reinforcements with consideration of residual interfacial shear strength

Abstract

Interface mechanics has always been a hot issue in geotechnical engineering, particularly in reinforced soil structures, but most existing numerical evaluations still used ideal elastoplastic models to predict the interaction of the reinforced soil surface, resulting in imprecise results. In this paper, based on a sophisticated analytical solution, a finite element analysis method was proposed for analysing the pull-out behaviour of embedded planar reinforcements considering the residual interfacial shear strength. In the numerical model, an improved cohesive element, which can precisely characterize realistic tri-linear shear slip models basing on a tabular function, was employed to simulate full-range progressive pull-out behaviour. Meanwhile, the parameters of the tri-linear shear slip model can be simply calibrated from pull-out tests using the proposed analytical solution, and the calibrated shear slip model can subsequently be used for modelling more complex problems. The finite element model was verified by two pull-out tests, and a parametric study was carried out for providing insights into the pull-out behaviour of embedded planar reinforcements. The results show that increasing the reinforcement length, the residual shear strength factor and the overburden pressure can improve the interface ductility and the ultimate pull-out capacity; Increasing the reinforcement stiffness improves the ultimate pull-out resistance increases but decrease the ductility.