Ultra-High-Strength Engineered Cementitious Composites (UHS-ECC) panel reinforced with FRP bar/grid: Development and flexural performance

In this study, Ultra-High-Strength Engineered Cementitious Composites (UHS-ECC) panels with Fiber-Reinforced Polymer (FRP) reinforcement (i.e., FRP bars and girds) were proposed for the construction of sustainable marine structures. Based on four-pointed bending tests, the mechanical performance of FRP-reinforced UHS-ECC [with 2% polyethylene (PE) fibers] and FRP-reinforced ultra-high-strength concrete (UHSC, without fibers) panels were investigated and compared to understand the composite action between UHS-ECC and FRP. Compared with the FRP-reinforced UHSC panel, the FRP-reinforced UHS-ECC panel showed significantly higher ultimate load (139-173% higher), stiffness, and deformation capacity. It was also found that the use of seawater as the raw material had almost no effect on the mechanical performance of FRP-reinforced UHS-ECC (UHSC) panels. An analytical investigation was conducted to predict the load capacities of the tested panels, and the prediction error was acceptable. For FRP-reinforced UHS-ECC (UHSC) panels, it was revealed that using UHS-ECC to replace UHSC improved the stress transfer and deformation compatibility with FRP because the multiple cracking behavior of UHS-ECC lowered the crack-induced shear stress concentration along the FRP reinforcement. The developed FRP-reinforced UHS-ECC system showed great potential in the construction of durable and sustainable marine infrastructure.