The analysis of unpaved roads subjected to the heavy axle load (HAL) is a challenging task that requires a comprehensive understanding and meticulous attention. The application of HAL on unpaved roads is one among the major factors contributing to non-recoverable deflections causing ruts and permanent deformation. The guidelines in the codal provisions for designing unpaved road are prescribed for standard axle load with a maximum gross vehicle weight (GWA) of 15 tons. However, the vehicles, namely haul trucks in mining and forest areas, military tanks, and heavy excavators on unpaved roads, exceed the standard limits. The use of geosynthetics to provide reinforcement is very effective in increasing the load-carrying capacity of unpaved roads subjected to standard axle load. However, the studies on the utilization of geogrid in the unpaved road under the application of HAL are meager. The present work aims to fill up the void by numerically simulating the behavior of geogrid-reinforced unpaved road under the application of HAL. The influence of HAL on load–displacement and stress–strain with varied configuration of geogrid have been investigated. The observation suggested a compounded relationship among HAL, load–displacement, stress–strain, and geogrid configuration. This compounded behavior may be attributed to the property of material and the magnitude of HAL. The findings are expected to contribute significantly to the sustainable development of transportation network.