Evaluation of limestone crushed dust aggregates in hot mix asphalt

- Laboratory evaluation of HMA mixes with granite and limestone aggregates were investigated.
- Using limestone in fine fractions improved the mechanical behavior in HMA mixes.
- Limestone as filler in HMA mixes can improve permanent deformation resistance.
- The results confirmed the efficiency of limestone as fine fraction and filler in HMA mixes.
- HMA mixtures with granite and limestone aggregates met Brazilian specifications.

The growing demand for aggregates in highway infrastructure makes necessary to search local materials. The objective was to evaluate the inclusion of limestone aggregates in hot mix asphalt mixtures, through laboratory tests. The HMA mixtures were designed by Marshall and Superpave and submitted to indirect tensile-strength, resilient modulus, moisture damage and Flow Number. It was found that HMA mixtures with limestone showed better mechanical behavior, contributed for stiffness and gain of mechanical resistance, mainly to permanent deformation. Relative to moisture damage results, all mixtures were susceptible to water, but even so are technically viable for use in surface courses.