Reinforcement of recycled aggregates stands as a pivotal strategy to stimulate their resource utilization. This study proposes a strengthening method of recycled aggregate combined with particle molding and vacuum cement coating, and the key control parameters in the reinforcement process, resultant reinforcement outcomes, failure modes, and water absorption kinetics were discussed. Experimental findings suggest that diminutive surface particle sizes present amplified challenges for shaping. The particle strength within each size categories demonstrates an initial ascent followed by descent with prolonged shaping, underscoring an optimal reinforcement duration. Excessive shaping precipitates a decline in the property of recycled aggregates, manifested through fracture, crush, and local damage. The moisture content of recycled aggregates undergoes fluctuations throughout the shaping process. Notably, the application of vacuum cement coating markedly ameliorates water absorption post-particle shaping, thereby augmenting failure mode resilience. Building upon these observations, the framework of “moderate shaping,” “moderate damage,” and “damage-repair integration” is introduced for both internal and external reinforcement. This paradigm aims to bolster the particle strength of recycled aggregates, thus facilitating water conservation during the scale-up preparation phase. This study can guide the establishment of production facilities tailored for recycled concrete and furnish insights for the scaled-up preparation of recycled concrete materials.

Keywords: Recycled aggregate, Particle shaping, Vacuum cement coating, Failure mode, Particle strength.