Analysis of Twin Large Circular Footings on a Geocell-Reinforced Bed Using Response Surface Method

Abstract

The pressure-settlement response and failure mechanism behavior of two interacting rigid rough identical footings resting on geocell-reinforced sand is investigated using finite-difference software, FLAC3D. The geocell is modeled with the actual shape considering the inclusion of the interface element. The numerical simulation is validated with experimental investigations and then parametric studies are conducted on the geocell geometry at different spaces between footings, simultaneously. A mathematical formulation is proposed to obtain the improvement factor using response surface methodology as a subdivision of the design of experiments method. Comparison between the simulated results with performed test results and previous investigations shows an excellent agreement. The derived mathematical expression shows the optimum values of 0.1 and 0.35 times the footing diameter for embedded depth and height of geocell-reinforced soil, respectively. The maximum edge-to-edge distance of twin footings with no influence on each other is approximately 3.5 times the footing diameter while the maximum improvement factor is obtained when two footings are beside each other with no clear distance.