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Predicting the mechanical properties of normal and high strengths concrete modified with fly ash at different w/c ratios, and curing times

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Abstract

The objective of this study is to identify and quantify the effect of fly ash content (FA), water/cement ratio (w/c), and curing time (t) on the compressive and tensile strengths of concrete at different strength ranges varied from 4 to 100 MPa. More than 1000 experimental data collected from different research studies. Statistical analysis and modeling were performed on the collected data. The range of w/c ratio for modified concrete with different percentages of fly ash up to 90% (by dry weight of cement) was 0.19–0.87. Compressive strength (cs) and tensile strength (ts) were 4–100 MPa and 0.5–6 MPa respectively. Vipulanandan correlation model was used to predict the relationship between mechanical properties of concrete modified with FA. Based on the coefficient of determination (R2) and root mean square error (RMSE) the compressive strength (cs) and tensile strength (ts) of concrete as a function of w/c ratio, FA content, and curing time quantified very well using nonlinear (NLM) relationship. Based on the NLM parameters, the effect of FA was less than w/c ratio and curing time on the compressive strength of modified concrete in different strength ranges.

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  1. Department of Civil Engineering, College of Engineering, University of Sulaimani, Sulaymaniyah, Kurdistan Region, Iraq

    Kawan K. Ghafor

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Ghafor, K.K. Predicting the mechanical properties of normal and high strengths concrete modified with fly ash at different w/c ratios, and curing times. J Build Rehabil 5, 24 (2020). https://doi.org/10.1007/s41024-020-00088-w

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