Shear failure mechanism and parametric study for seawater sea-sand engineered cementitious composites beams reinforced by FRP bars: Finite element analysis

Seawater sea-sand engineered cementitious composites (SS-ECC) is recommended to be used in combination with fiber reinforced polymer/plastic (FRP) bars, which is beneficial to mitigate the lack of raw materials in offshore construction. In this study, finite element analysis was carried out to investigate the shear behaviors and failure mechanism of SS-ECC beams reinforced by FRP bars. The proposed finite element models were verified by the shear experimental results of SS-ECC beams with or without stirrups. It is observed that the shear behaviors of SS-ECC beams can be effectively reflected by the finite element models. Moreover, the shear failure mechanism of SS-ECC beams was carefully analyzed. SS-ECC in beams exhibits serious damage in the compression-shear zone, while FRP longitudinal bars and stirrups are not destroyed. Parametric study, including matrix material, shear span ratio and stirrup ratio, was conducted on. For stiffness and peak shear load, SS-ECC beams with stirrups are almost unchanged with the increment of stirrup ratio, which is due to SS-ECC's failure rather than FRP stirrup rupture. In addition, the prediction method for shear capacity was further validated by the numerical results. The findings of this study lay a foundation for the engineering applications of SS-ECC beams.