The Replacement of the Parts of the Aggregate in Concrete with Chalcedonite Powder

In recent years, many researches have been conducted concerning the influence of chemical admixtures and mineral additions on the properties of concrete mixture and the parametres of hardened concrete. The current state of knowledge is not sufficient for effective use of concrete mixtures with the addition of chalcedonite powder. The development of concrete mixture, in which a part of the aggregate is replaced with chalcedonite powder can become an alternative to concrete as it creates the possibility of management of waste located near the chalcedonite aggregate mines. Chalcedonite powder has the same properties as the aggregate it is created from. That means it is not dangerous but has a negative impact on the natural environment. Obtaining chalcedonite powder is not expensive and will not only lower the costs of concrete mixture production but also have a positive impact on the environment.The article discusses the results of the laboratory tests on the influence of chalcedonite powder on the physico-mechanical properties of concrete. The meal replaced the aggregates in the amount of 5%, 10%, 15% by their mass. The amount of cement was unchanged. The research concerned the rheological properties of concrete mixtures, i.e. consistency, density, degree of aeration and the parametres of hardened concrete, e.g. compressive strength, capillarity and water absorbability. The addition of meal leads to the decrease in compressive strength. The decrease is related to the amount of the chalcedonite powder in the concrete mixture. Improvement was noticed in water absorbability and capillarity.