Evaluation of the Bearing Capacity of Sandy Soils with Analytical and Numerical Methods

Abstract

In the present study, the bearing capacities of coarse graded soils beneath shallow strip foundations at the surface (D f =0) were calculated by means of analytical and numerical methods. First, all necessary geotechnical properties of the soil were achieved at seven different relative density values of the soil in terms of correlations between friction angle (ϕ) and dry density (γ d ). Second, 56 bearing capacity analyses of shallow strip foundation systems at surface were conducted by changing the soil parameters and the width of the foundations with analytical and finite element methods (FEM). The Mohr-Coulomb, elasticplastic, model was chosen for this research. Although explicit analytic solutions were obtained without any difficulty, FEM provided only the load-deformation response at the base of the footing from the models. Because of that, some prediction methods were used to evaluate and find the bearing capacity of the soils beneath the foundation from the load-deformation responses. The results of analytic and numerical analyses of the shallow strip foundation laying on loose soil models gave very similar values. Although, very similar bearing capacity values of the foundations laying on dense soil models were calculated using analytical methods, the results of numerical methods were very divergent and scattered at the same conditions. The reason for this is due to some limitations of the elastic-plastic model and prediction methods.

Experimental Study of Bearing Capacity Bridge Foundation Determination

“…The ability to predict bearing capacity and footing settlement accurately is critical in foundation design and impacts overall project cost [12]. The bearing capacity equations for conventional footings (strip, square, circular, and rectangular) are well established and documented [13]. However, for economic and architectural reasons, unconventional shallow footing geometries were sometimes required [14].…”