Design Charts for Geogrid-Reinforced Granular Working Platform for Heavy Tracked Plants over Clay Subgrade

This study investigates the bearing capacity of a geogrid-reinforced granular working platform for heavy tracked plants on clay subgrade using a 2D plane strain finite element method. It substantially extends a case study investigated by incorporating wider soil parameters, depth-to-width ratios and geogrid stiffness modulus. The developed models are first verified by comparing them with the published literature and found to be in good agreement. The parametric modelling results are then used to develop a comprehensive set of design charts with non-dimensional parameters, bearing capacity ratio verses shear strength ratio, so that they can be directly used by practitioners. With the help of a design example, minimum design thickness of the granular working platform is compared and benchmarked with other established design methods. The results show that the proposed design charts and methods are comparable and provide reasonable predictions for the bearing capacity and working platform design thicknesses. A design example shows that thickness of the geogrid-reinforced granular base could be reduced from 1.2 to 55.6% for different geogrid strengths whereas the reduction is very nominal for soft geogrids ranging from only 1.2 to 3.0%.