Surface Fraction Measurements of Fine-Graded Asphalt Mixtures; Final rept. for 1 Jul 04-12 Sep 07

摘要

Skid resistance is generated by the development of friction between the vehicle tire and roadway surface, and is partially dependent upon the characteristics of the pavement texture. Microtexture and macrotexture are the critical components of pavement surface friction. Microtexture is the dominant characteristic at low speeds, and at high speeds, microtexture and macrotexture are both necessary. While these parameters are very important, neither is considered during the design of an asphalt mix. In this project, mixture design parameters were investigated to determine what features of 4.75mm hot-mix asphalt (HMA) mixtures significantly influenced skid resistance. The British Pendulum Test (BPT) was used to quantify microtexture, and a sand patch test (modified for laboratory use) was used to measure macrotexture in terms of texture depth. Mixture properties and aggregate properties were also analyzed in order to develop relationships and guidelines for producing skid resistance during the design phase of an HMA construction project.