This pioneering study successfully explored the potential use of crumb rubber aggregates (CRA) in rubberized concrete (CRC), focusing on particle size distribution, packing optimization, and CRA content, as well as their interactive effects on the compressive strength (CS), physical properties, and environmental impact (EI). By replacing natural sand with CRA particles at 10~30% content, a novel total gradation deviation (TGD) metric was introduced to optimize the aggregate packing. The corresponding results indicated that CS of CRC is influenced by CRA size, water absorption (WA), CRA content, and TGD. However, no definitive correlation was observed between CRC density and structural integrity. Whilst the 28-day cured concrete indicated that optimal CS (~23 MPa) was achieved at 20% CRA, efficient particle packing was attained at 10% CRA content. Consequently, there was a reduction in energy demand and CO₂ emissions by 10~22.3% and 5~10%, respectively. The engineered concrete formulation is suitable for diverse lightweight applications, such as foundations, slabs, and load-bearing blocks in low-rise construction projects, as well as residential driveways and pedestrian walkways. Furthermore, CRA replacement was found to reduce the EI without necessarily decreasing the cement consumption. Notably, larger CRA particles (>0.6 mm) lowered the EI by up to 33%, but undesirably reduced the strength by 65%. Overall, the study contributes to eco-friendly CRC solutions that align with the United Nations (UN) Sustainable Development Goals.
https://ssrn.com/abstract=5198130 or http://dx.doi.org/10.2139/ssrn.5198130