Behavior of Fiber Reinforced Concrete Beams with Inadequate Torsion Steel under Pure Torsion

To investigate the relationship between reinforced concrete beams under pure torsion and steel fiber usage, 16 large-scaled reinforced concrete beams with inadequate torsion steel were designed and produced. For experiments, a new test setup was designed to allow specimens to have rotational movement on one end and axial movement on the other end. The variables were selected as 300 and 400 mm spacings of transverse reinforcements and 0.0%, 0.3%, 0.6%, 0.9%, 1.2%, and 1.5% by volume of the mixture as steel fiber ratios. Cracking torque, maximum torque and ultimate torque values were obtained experimentally, and torque-twist curves and energy dissipation capacities were determined. Findings were compared to indicate the relationship between variables. Results showed that certain values of steel fiber ratio as a replacement material for relevant spacing of transverse reinforcements.