Bearing Capacity of Strip Footing Placed on the Reinforced Soil Slope

Abstract

In this study, the bearing capacity of a strip footing placed on the top of a cohesionless soil slope was computed with the use of lower-bound finite-element limit analysis. A single layer of reinforcement was placed below the footing at various depths. The magnitude of Nγ, which is related to the unit weight of soil, was computed by varying the slope angle (β), footing setback distance (b), soil friction angle (ϕ), and depth of the single layer of reinforcement below the footing base (d). As expected, with the use of a reinforcement layer, the bearing capacity increased. The efficiency of reinforcement is expressed by the term ηγ, which is the ratio between the Nγ values obtained for the reinforced and unreinforced slopes. It was observed that ηγ increased with an increase in d up to a certain critical depth (dcr), after which it decreased. The obtained results are presented as design charts. The axial tension that developed along the reinforcement layer because of the footing load was also calculated, and the variation of the axial tension along the length of the reinforcement is presented graphically. The optimum length of the reinforcement (Lopt) was also computed. The results attained from the present study were compared with the available results from the literature. In addition to the extensive research regarding the foregoing parameters, the effects of ground inclination (α), soil layering, and the water table were also investigated by placing a strip footing on the edge of the cohesionless soil slope. Failure patterns are plotted for some representative cases.