Multiscale Modeling of Anchor Pull-Out in Sand

Anchors are popular and economic solutions for onshore and offshore engineering to provide adequate resistance for structures. In anchor design, it is critical to evaluate the bearing capacity of soil in supporting an anchor and understand the underlying load-carrying and failure mechanisms. Herein we employ a newly developed multiscale modeling tool based on coupled MPM/DEM for large deformation problems to investigate the cross-scale behavior during the pullout of plate anchors. This multiscale approach invokes Material Point Method (MPM) to tackle the large deformation problems in macro-scale and employs Discrete Element Method (DEM) to reproduce the soil response in meso-scale. It helps bypass conventional phenomenological constitutive models while providing cross-scale information of any interesting macroscopic observations. In this study, the influence of relative density of sand and the embedment ratio on the behavior of anchors (e.g., bearing capacity of anchors, deformation patterns) is investigated by the coupled method. Mesoscopic data and analyses originated from particle scale interactions are provided in lieu of the variable failure patterns observed in soil around an anchor during the pull-out process.