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Blended Portland cement‐ceramic powder binder containing up to 60 % fine‐ground waste ceramics from a brick factory is used in concrete mix design as an environmentally friendly alternative to the commonly used Portland cement. The experimental analysis of basic physical characteristics, mechanical and fracture‐mechanical properties, durability properties and hygrothermal characteristics shows that the optimal amount of ceramic powder in the mix is 20 % of the mass of blended cement. The decisive parameters in that respect are compressive strength, liquid water transport parameters and resistance to de‐icing salts, which are not satisfactory for higher ceramics dosage in the blends. In the case of other parameters studied, the limits for the effective use of ceramic powder are higher: 40 % for effective fracture toughness and specific fracture energy, 60 % for frost resistance and chemical resistance to MgCl2, NH4Cl, Na2SO4, HCl and CO2. The water vapour diffusion coefficient is found to increase with increasing ceramics content, which for wet envelopes can be considered as a positive feature, but may have a negative effect for dry envelopes. The thermal conductivity of all mixes increases fast with growing moisture content; differences of up to 50 % between the dry and water‐saturated state values are observed. This has to be taken into account in energy‐related calculations.

The possibilities of utilisation of ceramic powder as supplementary cementitious material are the matter of the presented study. The finely ground ceramic powder originates from the grinding process of thermal insulating brick blocks and shows pozzolanic properties. For the determination of its influence on concrete properties, five mixtures with different percentages of cement replaced by ceramics are designed. The bulk density as well as matrix density are found to decrease with the increasing dosage of waste ceramic material, while the open porosity increases. The compressive strength exhibits a small decrease with the growing amount of cement replacement. The measurement of thermal conductivity shows that by adding ceramic powder the thermal insulating abilities of studied concrete are improved.

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Selected mechanical, thermal, hygric, and durability properties of several concrete mixes containing natural zeolite as partial replacement of Portland cement are studied and compared with reference concrete. Experimental results show that natural zeolite has a potential to replace a part of Portland cement in concrete in the building industry. However, it is shown that although from both environmental and economical points of view it would be desirable to use its highest possible amounts in concrete production, the extent of Portland cement replacement which could be chosen in preparation of concrete mixes has relatively strict limitations. Concrete with the replacement of Portland cement by natural zeolite in the amount of 20% by mass is found to be the most suitable solution among the analyzed mixes.

A possible use of waste ceramic powder as a partial replacement of Portland cement in blended binders is studied. For the ceramic powder, originating from the contemporary hollow bricks production, the measurement of chemical composition is done using XRF and XRD analysis. The particle size distribution of ceramics and cement is accessed on the laser diffraction principle. The blended binders containing ceramic powder in an amount of 8, 16, 24, 32, and 40% of mass of cement are used for the preparation of cement pastes which are then characterized using the measurement of basic physical properties and mechanical properties. Experimental results show that an application of 16% waste ceramics in the blended binder provides sufficient mechanical properties of the paste. This makes good prerequisites for future research that will be focused on the development of new types of cement-based composites with incorporated ceramic waste powder.