Rheological behavior and fresh properties of self-compacting high strength concrete containing recycled PP particles with fly ash and silica fume blended

Solid waste management can be regarded as one of the major environmental concerns across the globe. Annually, substantial quantities of plastics are produced. The utilization of this waste can result in a variety of huge problems such as health hazards, disposal, and environmental pollution. In this paper, the workability and rheological characteristics of self-compacting high strength concrete (SCHSC) made with recycled polypropylene plastic particles (RPPP) with fly ash (FA) and silica fume (SF) are investigated. The SCHSC was employed by replacing the medium-coarse aggregate (MCA) with five percentages of RPPP contents at 0%, 10%, 20%, 30%, and 40% by volume. The first group of mixtures contained 20% FA and 80% Portland cement (PC). On the other hand, the second group of the mixes made with 20% FA, 10% SF, and 70% PC. To investigate such workability related properties as slump flow diameter (SFD), T-50 slump flow time (SFT), V-funnel flow time (VFT), L-box height ratio (LHR), and L-box T-200 and T-400 flow times, 10 concrete mixtures were produced and tested. ICAR rheometer in the rheological testing of fresh SCHSCs was used to determine the rheological parameters. For all mixtures, the compressive strength was measured at 28 days. With respect to the experimental results of the current study, the Herschel-Bulkley and modified Bingham models can provide well defined rheological representations for SCHSC with RPPP. The mixtures containing a combination of FA, SF, and RPPP can have better fresh characteristics compared to those without SF. Moreover, all produced SCHSC mixtures can be at a satisfactory level with the limitations required for the fresh properties of SCC.