Performance of Vertically Confined Shallow Foundation on Reinforced Sand Under Concentric Loading

Abstract

AbstractIn a view to keep a check on the economy, several methods have been devised up to enhance soil strength characteristics, among which confinement is one of the emerging techniques. This paper presents the performance of vertically confined shallow foundation placed over multi-layered geo-grid reinforced sand under concentric loading and the results are validated using PLAXIS 3D software. Parametric variations like top surface dimension of vertical confiner (D) (1B, 1.5B, 2B), number of geo-grid layers (N), length of reinforcements (L), spacing (Y1…n) between horizontal reinforcements (0.25B, 0.5B, 0.75B, 1B) have been investigated with a constant depth (d/B = 1) (where d and B are the depth of vertical confiner and width of square footing). The results reveal that with an increase in top surface dimension of vertical confiner increases the bearing capacity of footing quite appreciably for the specified settlement (25 mm) and approaches the optimum value at D/B = 2 for a minimum spacing of 0.25B between horizontal reinforcements. It is also noticed that the number of reinforcement layers and their proper placement inside the confiner play a vital role in bearing capacity improvement. Overall, it can be inferred that the model test results are supported closely by the PLAXIS results.KeywordsVertical confinementGeogridModel testsConcentric loadingBearing capacity