Strength and Strain Properties of Concrete, Comprising Filler, Produced by Screening of Waste Crushed Concrete

The presented paper is dedicated to the topical issue of utilization of screenings waste crushed concrete, which is produced as a result of crushing of waste materials, formed during dismantling buildings and facilities, and a production of fine aggregate concrete on its basis. The paper presented analysis of economic situation in the region and results of the study of screened waste materials in order to increase efficiency of an application of that product as fine aggregate and fine-ground active filler for a production of fine aggregate concretes. Particle size distribution, mineral and chemical composition of waste crushed concrete were studied, as well as features of their structure, taking into account heterogeneity of crushed material. Transitional zone of secondary aggregate and cement matrix was studied and it was proved, that the strength of adhesion with cement matrix of grains of that kind of secondary material, produced from screenings of waste crushed concrete, is significantly higher, than strength of the grain itself, which is indicative of an active influence of that aggregate on a formation of both characteristics of structure of cement matrix and dense transitional zone between them. Optimal composition of multicomponent binders, comprising fine-ground filler, produced from screenings of waste crushed concrete, is designed. Compositions and properties of cement matrix based on the designed binders are studied. Compositions of concretes, based on multicomponent binders with anthropogenic filler, are obtained and their strength and strain properties are studied.