This paper analyses the generation and re-use of different types of industrial wastes. From examined wastes, blast-furnace slag and washed recycled concrete were prepared our tested concrete samples with dimension 150×150×150 mm. In these samples were fraction 0-4 mm replacement by blast-furnace slag with a range of variation from 0 to 100%. Fraction 4-8 mm and 8-16 mm were replacement by aggregate prepared from washed recycled concrete parts with a range of variation from 0 to 100% in both fractions. Concrete samples contained aggregate prepared form recycled concrete and blast-furnace slag, are tested after 14 and 28 days of hardening. From the obtained results follows that washed recycled concrete and blast-furnace slag can be successfully used as a natural aggregate replacement in concrete production and has not negative effects on the properties of hardened concrete. Before mass using of these selected wastes, some important properties (durability and corrosion) of recycled concrete and blast-furnace slag concrete are necessary to investigate.

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Waste valorisation in production of building materials can be improved by their modification using some treatment technologies. Subsequently, products prepared using these optimized raw materials can show better or even new properties. Utilisation of construction and demolition waste (C&DW) for production of building materials is discussed for a longer time world-wide, whether in the form of coarse aggregates or in the fine-grain form as a micro-filler or as a binder. Both of these forms show specific problems have to be solved for increasing the quantities consumed. Fine-grain form can be obtained by techniques like crushing, grinding and sorting as well as by their combinations.This article is aimed on the utilization of specific portion of fine-grain C&DW (ceramics, glass and concrete) for production of concrete mixes of higher fluidity. C&DW were modified by specific process (defined method of crushing followed by sorting of particles under 250 μm). This material was expected as a micro-filler - substitution of natural aggregate (NA) in 0/4 fraction to the extent possible, that the rules allow. Using relevant calculations, 40% dosage was found as complying with standard limit for the maximum content (600 kg.m-3) of particles of less than 250 μm in whole mixture including the relative share of cement and NA. In accordance with these limiting factors, standard recipes were designed. Amount of water, as well as dosage of plasticizer was adjusted during mixing in order to keep the water/cement ratio (max. 0.6) and flow class F5 – F6.Resulting water consumption and dosage of plasticizer are discussed in the terms of influence of tested C&DW on the consistency and bleeding of concrete. Generally positive effect of fine-grain form of brick, glass and concrete was found compared to the reference concrete not containing those additive fine particles.

The aim of this paper is to verify activity index (pozzolanic reactivity) of finegrained waste glass and clay brick. First part of this work consists from milling process with variation in milling parameters (time, grinding ratio) and determination (analysis) of the grain size distribution. Subsequently strength activity index is assessed for samples of particles size 50-60 μm. According to EN 450-1 method, tested samples does not reached an appropriate limit values as 25% substitute of cement. This result does not disqualify this type of construction and demolition waste as active additive in building materials but it is necessary improving their input parameters.