Methodology for the selection of the composition for the production of products of hard-pressed concrete with industrial wastes

Abstract

The article presents a method of designing and assigning the composition of the molding sand, which is based on the calculation and experimental approach to determining the composition, taking into account the quality of raw materials used and the requirements for the properties of the concrete produced products. The main technical characteristics of smallsize rigidly pressed products and requirements to them are given. The methodology of selecting the composition of the molding sand is discussed in detail. The method of nominal composition of molding sand is developed and presented in the form of flowchart. A step-by-step description of the flowchart is presented. Low water-consumption binder, man-made wastes - ash microspheres as a damping additive, traditional coarse and fine aggregates are used as raw materials. To determine the physical and mechanical properties of concrete in the products were tested for compliance with the requirements of regulatory documents. When carrying out researches, there were used generally accepted rules of evaluation of geometric sizes and indices of outer appearance of products, average density, water absorption and strength properties of concrete, abrasion of face layer surface of products, rules of assignment of requirements to frost resistance. Production of products according to the proposed composition and the recommended method of calculation of the molding sand will contribute to environmental protection, since the production waste is used in their manufacture.