ANALYSIS OF POZZOLANIC ACTIVITY OF FINELY DISPERSED CONSTRUCTION CERAMIC WASTE. PART 2: INDIRECT ASSESSMENT OF THE STRENGTH OF CEMENT STONE.

The article presents the second part of the study of the efficiency and rationality of using fine-dispersed waste of building ceramics as a component of a complex binder. An analysis of the pozzolanic activity of fine-dispersed waste of building ceramics was carried out by indirectly assessing the strength of cement stone. The effect of replacing part of the cement with ceramic powder from 5 to 40% depending on its dispersion was studied. It was confirmed that with an increase in the specific surface of the ceramic powder, the water demand of the material increases due to the increase in water consumption for its wetting. It is shown that the use of finely dispersed ceramic powder allows obtaining cement stone of various shades from pale sienna to medium brown and golden brown (according to the RAL Design catalogue). The results of determining the pozzolanic activity by the Chappell method and measuring the strength of samples with partial replacement of cement by ceramic powder, and the results of studying the obtained samples using X-ray phase analysis prove the manifestation of pozzolanic activity by ceramic powders. Finely ground construction ceramic waste can potentially be used as an active mineral additive that strengthens the structure of cement stone, reduces efflorescence and increases resistance to leaching. In addition, it is possible to use ceramic powder as a pigment to impart decorative properties to materials. Such a solution will contribute to increased resource conservation, a decrease in the amount of construction ceramic waste and its repeated involvement in the production cycle.