Possibilities of lightweight high strength concrete production from sintered fly ash aggregate

Heat power plants based on coal combustion are produced fly ash as a by-product. Fly ash is not only a by-product. It is due to its pozzolanic activity very useable as a fine additive to concrete in the building industry. It has not only environmental aspect, but also an economic. Potential of use of fly ash in cement concrete technology is only as an additive. But there is a technology of building material production, which use up to 100 % of fly ash in the "mixture". It is sintered artificial aggregate. It can be used for some filter layers, for lightweight flat roof, ceiling or for lightweight concrete composite. There can be made different strength classes of the concrete. It is possible also produce high-strength lightweight concrete reaching strength up to 55 MPa. The paper is about possibilities of different types of fly ash for artificial sintered aggregate to achieve the parameters of lightweight high strength concrete. An interesting aspect of evaluating the quality of the composite is also synergistic interaction of aggregate joined to a cement paste. (C) 2017 The Authors. Published by Elsevier Ltd.