Skid resistance and texture of compacted asphalt mixes evaluated by the IFI in laboratory

The performance of pavements is intimately related to their structural design and to their components. However, pavement friction is highly important as it is one of the factors which determine pavement safety. The number of crashes derived from wet skidding is reduced when a vehicle tire and the pavement surface experience more friction. Skid resistance and texture are vital safety characteristics which need to be considered when pavement mixes are tested in laboratory. The objective of this study was to evaluate skidding based on macrotexture and microtexture used in the International Friction Index (IFI). This study was conducted in asphalt mixtures slabs produced in laboratory. Two different mixtures grading (dense and gap) were produced using conventional asphalt and asphalt rubber. The characterization of the macrotexture and microtexture of asphalt pavements surfaces was obtained by the following tests: (i) British pendulum; (ii) Volumetric Method. IFI values were calculated through the pair of the parameters: Sp and F60. The results showed that the gap-graded mixture had greater texture in comparison to dense grade mixtures. Asphalt rubber mixtures improved the skid resistance compared to conventional mixtures. For the covering abstract see ITRD E144473.