Ultimate loads for eccentrically loaded model shallow strip footings on geotextile-reinforced sand

Abstract

A series of tests were carried out with an eccentrically loaded model surface shallow strip footing on reinforced dense sand to investigate the decrease of the ultimate loads with increasing eccentricity and to compare the experimental results with commonly used approaches such as Meyerhof's effective width concept and the customary analysis. An experimental system was produced and used to run the tests. The experimental system consists of a tank, model footing, sand, loading mechanism, etc. A single woven geotextile sheet was placed horizontally below the footing's base at a depth of half of the footing's width. Geotextile reinforcement increased ultimate loads when compared to the unreinforced cases. This contribution decreases with increasing eccentricity. The measured decreases in ultimate loads with increasing eccentricities in the unreinforced tests within the core (kern, middle third) are in good agreement with Meyerhof's approach, while customary analysis is a little on the conservative side. Outside the core, Meyerhof's approach is on the conservative side in this case. Decreasing ultimate loads with increasing eccentricity for the reinforced tests cases were in general agreement with customary analysis, although they are slightly greater. Use of geotextile reinforcement improves load-displacement performance of eccentrically loaded strip footing from the settlement perspective. In other words, footings supported on a reinforced subgrade can generally carry larger loads than unreinforced footings for the same level of displacement.