The influence of geometrical parameters on the strength of crushed stone used for the manufacture of asphalt mixtures

Abstract

Physical and mechanical properties of asphalt concrete mixtures have a significant impact on the condition, durability and reliability of pavement life throughout its service period. These properties depend not only on the bituminous binders and mineral powders selected for asphalt mixtures, but also depend on geometrical and physical properties of crushed stone. The requirements of aggregates, used for the manufacture of asphalt mixtures, for strength indices are indicated in Technical Specifications TRA ASFALTAS 08:2008 and TRA MIN 07:2007. For the analysis of these indices, physical and geometrical parameters of rock solid crushed stone (granite, dolomite and gravel) of different origins have been investigated. The performance of study on aggregates used for asphalt mixtures determined the values for flakiness and shape indices (FI and SI), impact value SZ, resistance to fragmentation LA and for the density of the dry particles (DDP) rd. The performance of statistical calculations of obtained results allowed determining the correlational dependence between the geometrical properties of crushed stone grains (FI and SI) and the geometrical and strengthening properties of crushed stone of the same origin.