Torsional performance of FRP bars reinforced seawater sea-sand engineered cementitious composites (SS-ECC) beams without stirrup: A numerical study

To alleviate the shortage of raw materials and tackle the challenge of steel corrosion, the authors used seawater and sea-sand to fabricate engineered cementitious composites (SS-ECC) beams and reinforced them only with fiber reinforced plastic (FRP) longitudinal bars. This article focused on the torsional behaviors of the SS-ECC beams through experimental and numerical studies. Finite element models (FEM) were established and well verified based on the torsional tests. The failure mechanism of the SS-ECC beams under pure torsion was carefully explored by analyzing the stress and strain distribution of SS-ECC at different positions. It is indicated that the SS-ECC beams with high fiber volume fraction tend to fail due to compressive damage. Furthermore, a parametric analysis was conducted to study the effects of various factors on the torsional performance. The strength grade of SS-ECC, rather than longitudinal reinforcement ratio and height/width ratio, makes the critical factor that determines the ultimate torque of the SS-ECC beams. This research lays the groundwork for under-standing the torsional performance of the SS-ECC beams without stirrup.