Imjai, T.; Garcia, R.; Guadagnini, M.; Pilakoutas, K. Strength Degradation in Curved Fiber-reinforced Polymer (FRP) Bars Used as Concrete Reinforcements. Polymers2020, 12, 1653.
Imjai, T.; Garcia, R.; Guadagnini, M.; Pilakoutas, K. Strength Degradation in Curved Fiber-reinforced Polymer (FRP) Bars Used as Concrete Reinforcements. Polymers 2020, 12, 1653.
Imjai, T.; Garcia, R.; Guadagnini, M.; Pilakoutas, K. Strength Degradation in Curved Fiber-reinforced Polymer (FRP) Bars Used as Concrete Reinforcements. Polymers2020, 12, 1653.
Imjai, T.; Garcia, R.; Guadagnini, M.; Pilakoutas, K. Strength Degradation in Curved Fiber-reinforced Polymer (FRP) Bars Used as Concrete Reinforcements. Polymers 2020, 12, 1653.
Abstract
Steel reinforcement in concrete has the tendency to corrode and this process can lead to structural damage. FRP reinforcement represents a viable alternative for structures exposed to aggressive environments and has many possible applications where superior corrosion resistance properties are required. The use of FRP rebars as internal reinforcements for concrete, however, is limited to specific structural elements and does not yet extend to the whole structure. The reasons for this relate to the limited availability of curved or shaped reinforcing elements on the market and their reduced structural performance. Various studies, in fact, have shown that the mechanical performance of bent portions of composite bars is reduced significantly under a multiaxial combination of stresses and that the tensile strength can be as low as 25% of the maximum tensile strength that can be developed in the straight part. In a significant number of cases, the current design recommendations for concrete structures reinforced with FRP, however, were found to overestimate the bend capacity of FRP rebar. This paper presents the state-of-the art review of the research works on the strength degradation in curved FRP composites and highlighted the performance of exiting predictive models for the bend capacity of FRP reinforcement. Recent practical predictive model based on the Tsai-Hill failure criteria by considering the material at marcromechanical level is also discussed and highlighted. The review also identifies the challenges and highlights the future directions of research to explore the use of shaped FRP composites in civil engineering applications and the trends for future research in this area.
Keywords
Curved FRP bars; bent fiber-reinforced polymer (FRP); bend capacity; bend strength; Bent test; strength & testing of materials; material characterisation
Subject
Engineering, Civil Engineering
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
