Torsional Behavior of Recycled Aggregate Based Glass Fiber Reinforced Self-Compacting Concrete

The quality and characteristics of concrete are profoundly impacted by factors such as compaction integrity and its inherently brittle nature. A promising solution to challenges related to compaction is Self-Compacting Concrete (SCC), which achieves consolidation without the need for vibrators. Despite its potential, there remains a need for comprehensive investigations, particularly concerning its behavior in torsion a fundamental structural action often overlooked but crucial for analyzing structures exposed to wind and seismic forces. The analysis of lateral loads on structures is where torsion really shines. The response of members to lateral forces is greatly affected by characteristics such as torsional rigidity, toughness, and twist at ultimate torque. Sustainable concrete development is aided by the incorporation of recycled aggregates, and glass fibres improve the material's energy absorption properties. Existing literature shows a lack of investigation into the torsional behaviour of SelfCompacting Concrete that is reinforced with glass fibres and recycled aggregates. To fill this void, we conducted a study comparing the performance of self-compacting concrete beams made with recycled coarse aggregate (at 20%, 30%, and 40% weight replacement) and glass fibre (at 0.5, 1, and 1.5 aspect ratios) to conventional Vibrated Concrete. We used both natural and recycled coarse material to cast 16 beams to 30 MPa. Our results show that self-compacting concrete with either natural or recycled coarse aggregates has significantly better torsional properties than vibrated concrete in terms of ultimate torque, angle of twist, torsional stiffness, and torsional toughness. The incorporation of fibres also contributes to this enhanced functionality. As an example, researchers found that members with fibre aspect ratios of 1.5 in selfcompacting concrete and 0.5 in conventionally vibrated concrete had the best performance. Furthermore, it was discovered that a ratio of 40% recycled aggregate was ideal for both self-compacting concrete and conventional concrete. In summary, this study underscores the significant potential of self-compacting concrete, especially when enhanced with glass fibers and combined with recycled aggregates, to achieve superior torsional properties. These findings hold implications for enhancing the performance and sustainability of concrete structures.