CEMENTITIOUS MATERIALS DEVELOPED BY THE USE OF LOCAL MINERAL ADDITIONS (INDUSTRIAL BY-PRODUCTS AND WASTES).

The positive effect of mineral additions in cementitious materials (concrete, mortars, composite materials), proven by several studies along time, encouraged a complex research at NIRD “URBAN-INCERC” Cluj-Napoca Branch regarding the potential valorisation of mineral wastes or by-products, generated by Romanian local industry, in new innovative cementitious materials for the construction industry. The central focus of the research was targeted towards fly ash and its potential use in reliable, high performance cementitious compositions, with innovative, ecological features for the construction industry. Still on large production in Romania, generated by coal power plants in the energy industry, fly ash is not properly valorised, being rapidly converted from a valuable by-product (with potential use in cement and concrete additions, mortar for soil stabilizing mortars, road infrastructure etc.) to a harmful waste, landfilled in the vicinity of the plant. Statistical data confirms that less than 0.06% of the total industrial waste generated (fly ash, boiler slag, etc.) was successfully re-integrated as raw materials for new, different purposes. The aim of this paper is to present the first results regarding the typology of cementitious composites, where fly ash was successfully integrated as addition/partial replacement of cement: concrete and Fibre Engineered Cementitious Composites (FECM). The potential matrix compatibility with other waste mineral additions like slurry lime or bottom ash and relevant aspects regarding materials performance in terms of strength and durability are also presented. [ABSTRACT FROM AUTHOR]