The researches results of the fuel ash waste’s and grain crops straw’s influence on the properties of the producing expanded clay gravel are presented in the paper. These wastes were used as auxiliary additives in the raw combination. The optimal composition of the raw combination has been established in the laboratory, for which physical and mechanical characteristics of the samples, including water absorption, compressive strength, bulk density, were analyzed. Characteristics of the expanded clay gravel samples are compared with the state standards requirements. It was found, that the addition 5% fuel ash and 1.5% crop waste (grain straw) ensures optimal swelling of the combination and high strength characteristics of the finished product.

Keywords: expanded clay, fuel ash, waste of crop production, swelling, construction materials, porosity.