USE OF IRAQ CONCRETE SCRAP AS FILLER AND AGGREGATE OF HEAVYWEIGHT AND LIGHTWEIGHT CONCRETE

Abstract

the relevance of the paper is due to the search for alternative sources of raw materials for the construction industry, associated with the disposal of man-made waste. The novelty of the article is to identify the scien-tific laws of the influence of demolition waste on buildings and structures on the formation of the micro-structure of lightweight and heavyweight concrete. Concrete waste was prepared as both fillers of cement materials and fine aggregates, based on which concrete with high mechanical properties was created. The mix design was carried out from the point of view of geomimetics, in particular, taking into account the law of affinity of structures. The strength characteristics of concrete mixtures were investigated in accordance with EN 12390-3. In addition, the microstructural, morphological and thermal properties of the raw materials and concrete were determined during 28-day curing. For the first time, the dense microstructure of the com-posite was ensured, both with Portland cement products and with hydration, and, in part, with hydration products of previously unreacted clinker, whose minerals are present in concrete waste and are activated when they are crushed. The use of demolition waste of buildings and structures as a filler of cementing ma-terial when replacing Portland cement up to 20% allows to obtain better compressive strength of both heav-yweight and lightweight concrete.