Multiscale Evaluation of Inclined Loading Effects on Horizontal Plate Anchors in Sand

A multiscale approach that couples the FEM and discrete-element method (DEM) was utilized to investigate the mechanical response of slantingly loaded horizontal plate anchors in sand. This multiscale approach overcomes the limitations of conventional constitutive models by directly obtaining the sand constitutive relations from the DEM simulations on the representative volume elements (RVEs) attached to the FEM Gauss points. The bearing capacity of the plate anchor under different load inclinations was effectively captured using the multiscale approach and validated against available experimental data and FEM simulations using traditional constitutive models. The anchor capacity was observed to increase as the load inclination approaches the horizontal direction. Further investigation of the failure mechanism indicated the presence of an inverted trapezoidal soil block in the postfailure state for load inclination θ≤60∘, while a more localized failure mode was observed for θ≥75∘. As θ increased, cross-scale analyses based on the contact normal-based fabric tensor revealed a clockwise rotation of the major principal directions within the RVEs above and below the anchor, while the major principal directions in the RVEs to the right of the anchor shifted to a more horizontal orientation. These observations on the evolving microstructures of RVEs explain the microscopic origin of the higher peak bearing capacity values observed for higher load inclination angles.