DEVELOPMENT OF HEAT-RESISTANT CONCRETE BASED ON CORUNDUM MATERIALS FROM MAN-MADE WASTE

The article presents the results of the development of heat-resistant concrete using technogenic wastes containing corundum. An aluminophosphate binder was employed as the binding component, while refractory clay was used to modify the composition. Experimental studies demonstrated that the incorporation of clay and the optimization of component ratios significantly improved the performance characteristics of the concrete, particularly its strength and resistance to thermal loads. It was established that the optimal ratio of components increased the compressive strength to 62–65 MPa under normal conditions, with the best specimens reaching up to 75 MPa. After heat treatment at 1000 °C, the compressive strength remained in the range of 30–40 MPa, which corresponds to more than 60% of the initial value. The ultimate load-bearing capacity of the specimens reached 168 kN, confirming the high structural performance of the material. The density of the specimens was 2.8–2.9 g/cm³, while water absorption did not exceed 6–7%, which meets the requirements for heat-resistant composite materials. Microstructural analysis confirmed the formation of a thermally stable phosphate matrix with a uniform distribution of corundum grains. The obtained results confirm the applicability of the developed material under high-temperature service conditions, particularly for the lining of thermal units in metallurgical industries