The Effect of Tire Under Inflation and Tire Anomaly on Pavement Structural Layers

Truck loading is an important factor in pavement design and road asset preservation. In addition to load weight spectra, roads are often subjected to uneven axle loading, lateral lane position wander, variable tire pressures and variable tire types. An important consideration in determining load impact is how the load traction state is distributed within a single vehicle and the impact on road primary response profiles. This paper is a study of the structural effects on the pavement layers caused by uneven tire load tractions as compared to a non‐uniformly distributed loading which is often assumed for pavement design, asset management and performance prediction purposes. Tire load distribution measurements were collected from sensors installed on traffic data collection sites. Based on the real world traffic stream data collected, the frequency of tires with low contact pressures was established. A nonlinear stress‐dependent three‐dimensional finite element analysis was performed on a typical rural road structure under various climatic field state conditions. Shear strain profiles were analyzed by various heavy truck loadings within the road structure. These findings show shear strain increases of up to 30 percent around the underinflated tire cases when compared to a uniformly distributed loading across all field state climatic conditions and traffic speeds. Based on these results, it is recommended load enforcement; pavement management and design of roads consider load distribution among tires within axle groupings, tire footprint distribution and lane distribution in addition to total axle group weights.