Comparing the Performance of Recycled Calcined Bauxite vs. Locally Available Aggregate as Components in High Friction Surface Treatment Applications

For safe driving, the proper level of pavement friction must be maintained. The capacity of a pavement surface to offer friction to vehicles during cornering maneuvers or crucial braking is improved by high friction surface treatment. Calcined Bauxite is the most often utilized high friction aggregate. Calcined Bauxite, a byproduct, was the priciest aggregate relative to other locally accessible aggregates due to its restricted availability. Bauxite is one source of aggregate that when recycled (processed) has high friction properties. The researchers therefore assessed the frictional performance of Calcined Bauxite compared to five alternatives: Meramec River Aggregate, Rhyolite, Earthworks, and two byproducts (Flint Chat and Steel Slag). These alternatives were collected because they were locally available and less expensive when compared to Calcined Bauxite. The dynamic friction, the British pendulum, and the aggregate image measurement system were among the performance tests. The impact of aggregate sizes (#4 – #6 and #6 – #8) on British pendulum number (BPN) values was examined for Calcined Bauxite and three alternatives (Meramec River Aggregate, Rhyolite, and Steel Slag). Aggregates of larger size exhibited higher BPNs than smaller-size aggregates with differences in values ranging from 0.8 to 7. The correlation between the coefficients of friction measured by the dynamic friction tester and the number of polishing cycles was examined, and it revealed an exponential relationship. Alternatives to Calcined Bauxite can be screened using percentages of texture and angularity indices changes following Micro-Deval abrasion. Meramec River Aggregate, Flint Chat, and Steel Slag were effectively recommended alternatives for Calcined Bauxite.