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(a) Compressive strength of cylindrical concrete specimens produced with different dosages for recycled aggregates Fig. 6 (b) Statistical Analysis for compressive strength of concrete.
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Recycled aggregate (RA) made from waste concrete is an environmentally friendly alternative to natural aggregate (NA) for concrete manufacturing. However, compared to NA concrete, concrete produced with recycled aggregates has poor characteristics. Supplementary cementitious materials (SCMs) can be used to enhance the poor properties of recycled ag...
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... influence of RA, PPFs and WSA on concrete compressive strength is presented at each curing age in Fig. 6 (a). RA was used to substitute coarse crushed stone at three levels, 0%, 50%, and 100%. At each replacement level and curing age, the most notable strength was observed in blends having both WSA and PPFs, followed by blends with 10% WSA but without PP fibers. Concrete blends with only PP fibers and no WSA presented minor compressive ...
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... that WSA promotes the formation of additional phases, which improves bonding with PPFs, thus fully compensating for weaker ITZs formed. Therefore, the combination of WSA and PPFs allows for the replacement of 50% of natural aggregates with minimal loss in strength development after 90 days (WSA-0 no fiber 63.8 MPa; WSA-10, with PPFs 60.2 MPa). Fig. 6 (b) shows a plot of compressive strength at 28 days for all mixes. Each point shown on the graph represents an average of three values. A simple statistical analysis of the plotted data was also performed, and a linear fit curve (line) was also presented for each data series along with the plot equation. It can be observed from the plots ...
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... (b) shows a plot of compressive strength at 28 days for all mixes. Each point shown on the graph represents an average of three values. A simple statistical analysis of the plotted data was also performed, and a linear fit curve (line) was also presented for each data series along with the plot equation. It can be observed from the plots shown in Fig. 6 (b) that the maximum compressive strength was recorded in the case of zero (0%) percent replacement of recycled aggregate followed by fifty (50%) percent replacement and then hundred (100%) percent replacement irrespective of the wheat straw ash addition as well as the presence of fibers. This is because the recycled aggregate has a ...
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... reinforcement bars. Hence its measurement is fundamental for engineers' design of concrete structures, especially for coastal and marine environments. Concrete samples were immersed in sodium chloride (NaCl) solution for 28 days to conduct a chloride penetration test. Values obtained from various mixes of chloride penetration tests are shown in Fig. 16. It was observed that PPFs don't significantly impact chloride penetration values. However, WSA seems to have a positive behavior against chloride penetration, as the samples with WSA showed lower chloride penetration values than WSA-free counterparts. The results agree with Althoey, F. and Farnam, Y. 2020 [88], who reported similar ...
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