Investigation of the Plastic Hinge in Reinforced Concrete Beams Strengthened with Polymer-Plastic and Steel Rebars

In recent years, the use of advanced fiber-reinforced rebars as an alternative to steel reinforcement in concrete structures has attracted widespread attention. One innovative product developed in this category is the polymer-plastic rebar, which exhibits high resistance to corrosion, low weight, and remarkable durability. The outstanding properties of this product make it a suitable option for corrosive environments and regions with high humidity. In this study, the behavior of the plastic hinge in reinforced concrete beams strengthened with polymer-plastic and steel rebars was numerically and analytically investigated using the Abaqus software. In the numerical modeling, three-dimensional concrete elements with a plastic damage model and one-dimensional rebar elements were employed. The effects of reinforcement ratio, rebar type, plastic hinge length, and concrete strength on the flexural behavior and ductility of the beams were examined. The numerical analysis results indicated that beams reinforced with polymer-plastic rebars possess high ductility and desirable ultimate strength. Moreover, the parameters of plastic hinge length and reinforcement ratio have a direct influence on energy absorption capacity and crack patterns. Finally, the developed numerical model was compared with reliable experimental results, showing a satisfactory agreement in terms of force-displacement curves and strain distribution at critical sections. The findings of this research can serve as a foundation for optimizing the design of reinforced concrete beams with polymer-plastic rebars under specific working conditions and for performance-based design approaches.

کلیدواژه ها:

Polymer-plastic rebars ، steel rebars ، plastic hinge ، ductility