Use of Sustainable Fine-Grain Aggregates in Cement Composites

The previous research and the analyses from various research centers indicate the usefulness of the aggregates obtained from waste in the construction materials technology, although their technical parameters are not always comparable to the properties of traditional materials manufactured on the basis of primary raw materials. However, with a very large variety of expected technical features, these slightly lower parameters may be sufficient for use in engineering facilities. Mortars and concretes are the most popular group of materials, where aggregates obtained from waste can be used without any problems. The presented characteristics of the properties of fine aggregates, which were produced by grinding concrete and ceramic debris, as well as the fragmentation of municipal sewage sludge, in connection with the properties of cement mortars, is a clear example of this. The study showed that the cement mortars, in which natural aggregate was replaced by waste glass with the same granulation, confirmed their usefulness as mortar for building masonry, or underlays for floors. However, the fact that carrying out the process of fragmentation of waste to adequately fine granulation on an industrial scale is highly inconvenient, cannot be omitted. There are no difficulties in obtaining the aggregates with larger grains, which are used in hardening unpaved roads or as a concrete component. Obtaining finer grains of recycled aggregate becomes more challenging. Overcoming this obstacle will make the fine-grained aggregates obtained through the recycling of waste materials a viable alternative to the natural aggregates. This will contribute to the reduction of the extraction of natural sands, and thus to the protection of the natural environment.