Stochastic Spatial Excitation Induced by a Distributed Contact on Homogenous Gaussian Random Fields

The contact between vehicle tire and pavement surface random field is typically modeled as a point contact in the literature of vehicle-pavement interaction. In reality, tire-pavement interface can be considerably larger than a point contact, particularly when a tire is not very stiff and pavements are relatively soft. This paper developed a methodological framework that approximately aggregates one- and two-dimensional random fields within the contact area by taking local, weighted spatial average to account for the distributed contact. Statistical properties such as power spectral density, autocorrelation function and variance of the induced spatial excitation are related to the counterparts of the original random field. It was found that the distributed contact acts like a low-pass filter whose bandwidth is governed by the contact interface and the weight function.