An Investigation on the Effect of Aggregates Packing Density on the Properties of High-Performance Concrete Mixtures

Abstract

This study aims to investigate the influence of dry packing density of aggregates on themechanical and durability properties of high-performance concrete (HPC) mixtures. For this purpose, fourdifferent aggregate gradations were investigated, including ideal Fuller-Thompson curve (F), ideal Andreasen-Andersen curve (A) and their modified Funk and Dinger forms (MA and MF). The sequence of dry packingdensity of the aggregate gradations was as A >F>MA>MF. However, in contrast to the dry packing densityresults, the mixtures with the MF curve outperformed those with the other aggregate gradations in thedurability and mechanical properties. Likewise, the mixture with the ideal Andreasen-Andersen curve (A)had lower compressive strengths and a higher diffusivity. Thus, the results indicated that the packing densityof dry aggregates could not be indicative of the packing density of concrete and consequently the durabilityand mechanical characteristics of HPC. Moreover, the differences between the properties of the mixtureswere more evident at lower w/cm ratios especially at w/cm of 0.31. For instance, the difference between thecompressive strength of HPC mixtures with the MF and An aggregate gradations was about 14 MPa over 28days. This study has been carried out on the concrete mixtures with compressive strengths up to 110 MPa.