Full Factorial Optimization of Concrete Mix Design for Hot Climates

This paper presents the results of a statistical analysis aimed to optimize a concrete mix design for hot climates. A full factorial experiment with 3 × 4 × 4 × 3 treatment combinations (432) samples) of 48 mixes at three levels of temperature was used. The influences of the water/cement ratio (0.4, 0.5, and 0.6), coarse aggregate/total aggregate ratio (0.55, 0.6, 0.65, and 0.7), total aggregate/cement ratio (3, 4, 5, and 6), and temperature (24, 38, and 52°C) on compressive strength were characterized and analyzed using polynomial regression. Mathematical polynomials were developed for concrete strength as a function of temperature and mix proportion. Based on the statistical analysis, recommendations are provided on the optimum concrete mix for different temperatures as well as the mix that is least sensitive to temperature variations.