Study on the Uplift Behaviour and Failure Pattern of Single Belled Anchor with 3D and 2D Models in Cohesionless Soil Bed

Abstract

This study describes series of experimental investigations on the uplift capacities for 3D models of belled anchors and formation of respective nonlinear failure surfaces in sand around 2D panels. The variation in uplift capacities due to the influence of embedment ratios of 3, 4 and 5, diameter ratios of 0.28, 0.33, 0.38 and 0.46, and bell angles of 45°, 54°, 63° and 72° in dry sand is evaluated by 3D model study, and the present 62.5% experimental data are within a range of + 12.46 to − 15.14% variation based on a few previous multiple regression models. The observation on the variation of nonlinear failure pattern in sand around 2D panels is correlated with the effects of variable parameters. In order to visualise the pattern of failure surfaces clearly, 3-mm-thick layers of dyed sand are placed within 18-mm-thick non-dyed sand layers maintaining the same density of sand. The horizontal extent of failure points and corresponding embedment depth are plotted in X–Y coordinate. The mobilised shear and dead-weight of each slice wedge are evaluated by horizontal slice method, and vertical equilibrium is implemented for elementary forces. The variation in analytical uplift capacities is used to illustrate the effects of variable parameters. The variation of maximum horizontal extent of failure points at sand surface and passive, transition and active zones within failure domain is also illustrated. The experimental 81.25% data are within + 10.08 to − 9.74%, and rest are within + 15.85 to − 17% variation with respect to the analytical uplift capacities.