Measurement of Contact Stresses for Different Truck Tire Types To Evaluate Their Influence on Near-Surface Cracking and Rutting

Abstract

Two pavement distress mechanisms have become more prevalent in recent years: near-surface rutting and surface-initiated wheelpath cracking. Some possible factors causing these failure mechanisms include higher traffic volumes, use of lower-quality materials, and changes in tire type and structure. Although all of these factors may play a role, this study concentrated on the effects of changes in tire type and structure on surface distress. Within the last decade, trucking companies have shifted from operation on bias ply tires to an exclusive use of radial tires and the gradual introduction of wide-base (super-single) radial tires. This prevalence of radial tires causes a major change in pavement surface loading characteristics and is shown to help explain the development of surface rutting and cracking. Tire contact stresses were measured for bias ply, radial, and wide-base radial truck tires at various loads and inflation pressures to investigate the effects of tire structure, loading, and inflation pressure on surface loads applied to pavements. It was determined that contact stresses vary significantly for the different types of tires investigated. The observed variations were explained by the differences in tire construction. In fact, tire structure appeared to have a greater influence on contact stresses than variations in either load or inflation pressure for a given tire type. It was shown that the specific characteristics of the complex contact stresses under truck tires have a strong influence on asphalt pavement cracking and rutting and must be considered for proper design and evaluation of asphalt pavements.