Parametric study from laboratory tests on twin circular footings on geocell-reinforced sand

Document Type : Article


1 Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Department of Civil Engineering, K.N. Toosi University of Technology, Tehran, Iran

3 Faculty of Technology, University of Twente, Enschede, the Netherlands


Bearing capacity (BC) test results are presented for bounded and unbounded twin circular footings on unreinforced and geocell-reinforced (GCR) sand. Analysis of the results demonstrate material, scale and size effects on the BC for a given combination in materials (sand-GCR), footing (single-twin) and the problem geometric dimensions. The significance of these combinations on BC and settlements is used to arrive at suitably modified BC factors for design that could be generalized. Plots given relative to reference cases for which BC design solutions are available provide correction factors to modify classical BC equations. Values of the BC and BC factors represent the lumped effect of all or separate problem variables including scale and any experimental limitations. Compared with previous works, these results give deeper critical depths for twin footings on unreinforced and GCR sand and BC higher than 4 times the reference case.


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