Effects of Nonuniform Tire Contact Stresses on Pavement Response

Abstract

Since the 1960s, a uniform circular vertical contact stress has been used to model the tire/pavement interface in asphalt pavements. Recent experimental measurements show that this assumption cannot be used to model the actual interaction. This study investigated the influence of nonuniform contact stress distribution on the stress distribution and permanent deformation profile in asphalt pavements. A previous study measured the tire contact stresses between the pavement surface and moving pneumatic tires. Material properties of a hot mix asphalt mixture used at WesTrack were obtained from compressive strength tests within the framework of an elastic-viscoplastic constitutive model. A three-dimensional finite element (FE) analysis was performed based on boundary conditions and measured vertical stresses at WesTrack. The tire pressure distribution was dependent on the tire load and significantly influenced the pavement response. The FE analysis based on the elastic-viscoplastic model was able to simulate the measured permanent deformation profiles.