An Experimental and Numerical Study on the Bearing Capacity of Circular and Ring Footings on Rehabilitated Sand Slopes with Geogrid

Document Type : Regular Paper

Authors

Department of Civil and Environmental Engineering, Shiraz University, Shiraz

Abstract

This paper presents the results of a series of small-scale model tests and numerical analyses conducted on circular and ring model footings located near geogrid reinforced sand slopes. Layers of geogrid were applied as reinforcement. For numerical analyses Finite Element Method (FEM) was used. The effects of reinforcement depth, size, number of layers, and the horizontal distance between reinforcement and the slope surface were experimentally inspected. Moreover, the effects of other parameters such as slope angle, the distance of the footing from the slope crest (for circular footings) and the ratio of inner to outer diameters (for ring fittings) were also  numerically inspected. The results of numerical analyses were compared with the laboratory test results and found to be in fair agreement. Optimum bearing capacity values were found for some studied parameters. The results indicate that if the reinforcement layers are implemented correctly, the bearing capacity of circular and ring footings over slopes would significantly increase.

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