Prediction of Geogrid-Reinforced Flexible Pavement Performance Using Numerical Analysis

The finite element (FE) software PLAXIS 2D is used in this study to perform a numerical analysis for the prediction of deformation in the surface layer of geogrid-reinforced flexible pavements for various California bearing ratios (CBR) of subgrade and traffic volume. A linear elastic model was used to simulate the behaviour of base, sub-base, and subgrade soil, whereas geogrid was modelled as a linear elastic geogrid element. The accuracy of the FE analysis was verified by comparison of the outcomes of numerical studies to the findings of the experimental study reported by Correia, 2014. Using the validated FE model, this work has been extended to include geogrid into the base course of flexible pavement. A significant improvement in base layer modulus value was observed for geogrid-reinforced pavement when compared to an unreinforced case. Furthermore, the modulus improvement factor (MIF) for geogrid has been calculated based on the improved modulus value of the reinforced base layer. A comparison between two different types of geogrids, i.e. stiffness of 400 and 800 kN/m, is also analysed on the basis of MIF value.