Influence of various size crushed concrete waste aggregate on characteristics of hardened concrete

Abstract

The characteristics of hardened concrete depend on the raw materials used for the concrete mixture, their characteristics. Therefore, in the research, the variation of characteristics of concrete samples with concrete waste materials was analysed. During the analysis, concrete waste of different fractions was used as coarse and fine aggregate, as well as filler aggregate of crushed concrete waste was used. The research covers the implementation of X-ray analysis of the filler aggregate and identification of the main minerals of the aggregates produced from the concrete waste. The main physical and mechanical characteristics of the samples were determined through the implementation of the standard methodologies: the density of the samples was determined by following the standard LST EN 12390-7, compressive strength – LST EN 12390- 3; impregnation – LST 1428.18:1997. It was found that the physical and mechanical characteristics of the concrete, produced by using crushed concrete waste with different particle size, differ from the characteristics of the reference samples. However, these characteristics satisfy the requirements of the designed concrete class C30/37. The obtained results show that crushed concrete waste can be utilised as coarse and fine aggregates for the production of new concrete products.