Comparative study on properties of self-compacting rubberized concrete incorporating demolition and waste clay brick aggregates

The combined use of demolition brick aggregate (DBA) and discarded clay brick (CBA) with crumb rubber (CR) in a single concrete mixture remains largely unexplored. This study investigates the use of these two types of brick aggregate waste and their combined effect on the properties of self-compacting rubberised concrete (SCRC). In the proposed mixture, 100% of the sand and gravel were replaced with DBA or CBA, while CR was used at 10% as a volumetric substitute for natural sand. Slump flow, flow time, V-funnel, L-box, and segregation resistance were evaluated. Density and mechanical strengths were also determined, along with scanning electron microscope (SEM) analysis. Incorporating CBA enhanced the workability and increased the T500 value by approximately 30% compared to the DBA. In contrast, the inclusion of CR reduced flowability; however, the effect of CR on segregation resistance was not uniform in all mixes. Mixes prepared with DBA and CBA exhibited almost similar compressive strengths of 25.3 and 25.6 MPa, respectively. The combination of both brick aggregate types led to improved tensile strength and modulus of elasticity compared with mixes with a single type of brick aggregate. The proposed correlations provide a useful reference for future research in this field.