Analysis on the Mechanical Behavior of Steel Fiber Reinforced Concrete Members under Pure Torsion

Based on the skew-bending theory under elastic state and sand heap analogy under plastic state, a formula for computing the cracking torque of steel fiber reinforced ordinary concrete and high-strength concrete members tinder pure torsion has been established; the members having cracked under torsion were idealized as the spatial truss model of the thin-walled cylinder with the core concrete cross section in a solid beam neglected, steel fibers in thin-walled cylinder were considered equivalent to the longitudinal bars and stirrups in the reinforced concrete members when their volumes were equivalent, and a computing formula of ultimate torsion of steel fiber reinforced members under pure torsion was establish based on the space truss model theory. A comparison of the experimental data of 139 members from existing literature shows that the computing formula proposed by the paper is in excellent agreement with test values.