Evaluation of temperature effects on grade 20 concrete using response surface methodology

Abstract

This paper examined the evaluation of temperature effects on grade 20 concrete using response surface methodology. An experimental research design was adopted, which produced fifty-one (51) concrete specimens. The specimens were cured and tested at 7, 18, and 28 days, respectively. The specimens were exposed to temperatures of 20°C, 70°C, and 120°C for 1 h in an electric furnace, after the stipulated curing days. The results revealed the concrete compressive strength percentage loss at 70°C as 7.94% and at 120°C, the percentage loss as 16.5% when compared to the control’s compressive strength at 28 days curing duration. The ANOVA gave an F-value of 47.17 which was statistically significant and signifies that the quadratic model can predict the residual compressive strength of the concrete exposed to temperatures. It is thus concluded that temperature can affect concrete compressive strength negatively.