The results of optimizing the composition of concrete based on aggregates from crushed concrete are presented. With the help of mathematical and natural modeling matched the composition of the expanding agents sulfoaluminate type, the optimal percentage of components of the modified cement required for producing a material with improved performance characteristics, the mathematical model construction and technical properties of the concrete and the kinetics of their changes to take into account the time factor and strength and weathering.

Keywords: mathematical modeling, expanding additive, factor experiment, influencing factors, level of variation, experiment planning matrix