Behaviour of eccentrically loaded strip footings resting on sand

Abstract

This paper presents the results of experimental and numerical studies on the bearing capacity behaviour of an eccentrically loaded strip footing resting on geosynthetic-reinforced sand. The investigations were carried out by varying the footing width, load eccentricity, type of reinforcement and the relative density of the sand. Furthermore, finite-element analysis was conducted to evaluate the benefits of using reinforcement under eccentrically loaded strip footing. The results indicate that the footing width and load eccentricity have a great effect on the bearing capacity factor Nγvalues. For 1g models, the footing width B would be >110 mm, which is the smallest width of model foundation that should be used to determine the ultimate bearing capacity. At a load eccentricity (e/B) equal to 0·1, the ultimate bearing capacity increased by about 38 and 67% when the sand was reinforced with geotextile and geogrid, respectively. The difference between the ultimate bearing capacities obtained from the experimental results and numerical analyses varied from 10 to 14%. From prototype-scale numerical results, it was evident that the geogrid reinforcement increased the ultimate bearing capacity by about 12–24% when the load eccentricity (e/B) varied from 0·0 to 0·3.