Effects of packing on compressive behaviour of recycled aggregate concrete. (30th December 2017)

• Record Type: Journal Article
• Authors: Li, L.G.; Lin, C.J.; Chen, G.M.; Kwan, A.K.H.; Jiang, T.
• Is Part Of: Construction & building materials. Volume 157(2017)
• Page Start: 757
• Page End: 777
• Publication Date: 2017-12-30
• Subjects: FRP fibre reinforced polymer -- GGBS ground granulated blast-furnace slag -- OPC ordinary Portland cement -- PFA pulverized fuel ash -- M total mass of water-solid mixture -- RA recycled aggregate -- RAC recycled aggregate concrete -- RS river sand -- RS/TA ratio river sand to total aggregate ratio by volume -- SP superplasticizer -- ST specific toughness -- W/C ratio water to cement ratio by mass -- W/S ratio water to solid ratio by volume -- Rα Rβ and Rγ, volumetric ratios of α, β and γ to the total solid materials -- uw water to solid ratio by volume, same as W/S ratio -- V bulk volume of particles, i.e. volume of container -- Vs solid volume of particles -- ρα ρβ and ργ, densities of solid materials α, β and γ -- ρbulk bulk density of watersolid mixture -- ρw density of water -- ϕ solid concentration (ratio of solid volume to bulk volume; Packing density -- Wet packing density -- Recycled aggregate -- Recycled aggregate concrete -- Compressive behaviour; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2017.09.097
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Wet packing method was extended to measure packing density of recycled aggregate concrete (RAC). Workability and compressive behavior of RAC mixes were experimentally investigated. Strength, elastic modulus, toughness of RAC increase with increasing packing density. Packing density optimization is a promising way of improving the performance of RAC. Abstract: It is well known that the packing of particles in concrete has great effects on the performance of concrete, but codified methods for measuring packing density are all carried out under dry condition, which tends to result in loose packing due to agglomeration of the fine particles. Nevertheless, a wet packing method has been developed recently to enable more accurate measurement of packing density. In this study, this wet packing method was extended to measure the packing density of the concrete mix of recycled aggregate concrete (RAC). Furthermore, three groups of concrete mixes with various aggregate proportions and W/C ratios were produced for compression tests. It was found that at given W/C ratio and age, the compressive strength, elastic modulus, toughness and specific toughness of RAC would increase with increasing packing density, indicating that the packing density is a key factor affecting the compressive behaviour of RAC. Hence, packing density optimization is a promising way of improving the performance of RAC.