The road engineering community sees the increased use of recycled and marginal pavement materials as a key factor for more sustainable use of dwindling resources. However, successful use of alternative materials requires reliable models of pavement response and performance. In turn, these models depend on the accurate portrayal of tire/road contact stress distributions. Unfortunately, while the models have developed substantially, the acquisition of real stress distributions measured at full scale has not kept pace with the sophistication of the models. To solve the problem, it was recognized first that the measurement of tire/road surface contact stress distributions in all three of the vertical, longitudinal, and transverse directions needed to be facilitated. Second, a wide range of measured stress distributions needed to be used as input to models of pavement response and performance being developed. A multiphase project was conceived, to include (1) building an apparatus to measure contact stresses under full scale tires, (2) measuring contact stresses for a range of tire types, wheel loads, and inflation pressures, (3) characterizing the contact stresses as a function of tire type, wheel load, and inflation pressure, and (4) using the measured contact stresses as inputs to numerical models of pavement response and performance currently under development. The paper discusses the first three phases of the project.
