Improving Recycled Concrete Aggregates Quality by Optimizing Mechanical Treatment Parameters through Advanced Optimization Techniques

Abstract

The depletion of natural aggregate resources and increasing environmental concerns has driven the construction industry toward sustainable alternatives such as recycled concrete aggregates (RCA). However, the performance of RCA is often compromised by adhered mortar, which negatively affects its mechanical properties and durability. This study investigates the optimization of mechanical treatment parameters to enhance RCA quality using a Los Angeles abrasion machine. Advanced multicriteria decision-making techniques, including Taguchi, gray relational analysis, VIšekriterijumsko Kompromisno Rangiranje (VIKOR), and technique for order preference by similarity to ideal solution (TOPSIS), were employed to identify optimal combinations of abrasive charges and treatment durations. Key aggregate properties i.e., the specific gravity, water absorption, impact value, crushing value, and abrasion value were evaluated to assess treatment effectiveness. Results demonstrated significant improvements in RCA properties, with combinations such as eight abrasive charges and 30 min of treatment yielding superior performance. This study underscores the potential of optimized mechanical treatment in producing high-quality RCA, contributing to sustainable construction practices.