Mechanical and microstructural properties of self-compacting mortar produced using recycled polyurethane particles as aggregate

Developments in the construction sector and the increasing pace of the sector are in parallel with the increase in services such as transportation, accommodation and infrastructure that arise due to the growing world population. Construction materials such as concrete and mortar are largely based on sand and cement derived from the active exploitation of natural resources. The continuous extraction and utilization of these resources on demand causes significant environmental damage, leading to ecological degradation and resource depletion. Therefore, since sand/aggregate is one of the most intensively used natural resources in the production of concrete and its derivatives, the destruction of nature for its supply is rapidly increasing. In this study, polyurethane-based recycled materials (PUW), which are frequently used in industrial or domestic wastes, were substituted with aggregate in self-compacting mortar (SCM). In the mixtures used in the study, the water/binder ratio was 0.45 and the binder dosage was 500 kg/m3. PUW was substituted with aggregate at 5%, 10%, 15%, 20%, 20% and 25% by volume. The fresh, microstructural and mechanical properties of the SCM mixtures were comparatively evaluated to assess the basic requirements. The data from the mechanical tests of SCM showed that the 20% PUW replacement by volume remained above 30 MPa in the 28th day tests, which gives a basic indication of its suitability for use in terms of compressive strength.