Impact of contact stress distribution on skid resistance of asphalt pavements

In this study, the fractal dimension of the fracture surface was estimated to describe the surface roughness of four types of track boards in terms of utilizing the improved projective covering method. The results showed that Weibull distributions were applicable to describing the contact stress distribution between tire and pavement, and the Weibull expectation could effectively characterize the stress level. In addition, it was found that greater stress expectations indicated more significant stress concentration effects on the pavement surface. The stress distribution increased with an increase of pavement texture depth or tire load or a decrease of the tire inflation pressure. The influence of pavement roughness and tire load was more significant than tire inflation pressure on the stress concentration. Compared to the general pavement texture depth (sand patch method), the surface fractal dimension adequately described the surface roughness including macro-texture and micro-texture, and it was directly affected by the proportion of coarse aggregate. The pavement skid-resistance performance was mainly influenced by its high stress regions (>1.8 MPa) at the top of asperities. The skid-resistance performance of asphalt pavement was proved to be better with a high-level average effective stress.