This study investigates the torsional performance of reinforced concrete (RC) beams incorporating recycled crumb rubber (CR), steel fibers (SF), and recycled steel tires (ST). Seven half-scale RC beams were experimentally tested under pure torsion until failure. The key variables investigated include the CR replacement ratio as a partial sand substitute and the addition of SF and ST in varying proportions to evaluate their influence on torsional performance. The study assesses key performance metrics, including torsional moment capacity, angle of twist, crack propagation patterns, ductility index, failure mode, and stirrup strains. Experimental results reveal that replacing 10 % of sand with CR maintains a comparable torsional capacity to conventional RC beams. Moreover, a combination of 0.5 % SF and 0.5 % ST with 10 % CR achieved a torsional capacity equivalent to standard RC beams, demonstrating the feasibility of integrating recycled materials in structural applications. Furthermore, analytical models and code-based predictions were utilized to assess the influence of rubberized concrete containing ST and SF on torsional strength. These findings support the potential use of sustainable reinforcement materials in construction, offering a balance between structural efficiency and environmental benefits.
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