University of California Pavement Research Center

This report concentrates on the measurements of the three-dimensional (3-D) tire/pavement contact stress distributions for several pneumatic bias (or cross ply) and radial type tires used for Accelerated Pavement Testing (APT) at UCB and radial tires used by NATC at its Westrack test facility. The 3-D contact stress measurements were conducted with the Vehicle-Road Surface Pressure Transducer Array (VRSPTA) system. The VRSPTA system is in essence a “Stress-In-Motion” (SIM) system because it was developed to quantify the contact stresses between the tire and the pavement surface. As the VRSPTA system used for this study is the second prototype, it is referred to in this study as the “VRSPTA SIM Mark II” system. It was originally developed in South Africa for use in Accelerated Pavement Testing (APT) with the South African Heavy Vehicle Simulator (HVS).