Research on the Enhancement of Compressive Performance in GRPU Non-Destructively Reinforced Single-Limb Angle Connections

With the continuous expansion of the power grid scale and the increasing demand for electricity， the load demand of transmission towers continues to rise. Studying the non-destructive reinforcement of their key components is of great theoretical significance and practical value for improving their structural function and extending their service life. Lightweight and high-strength glass-fiber reinforced polyurethane （GRPU） is used to replace steel in traditional reinforcement， and the inclined angle （single-limb angle） commonly used in transmission towers is selected as the research object. A refined finite element model of the single-limb angle before and after reinforcement was established based on the non-destructive double-sided reinforcement scheme. A compression test of the single-limb angle was designed and conducted to verify the accuracy of the finite element simulation， and the effects of the two parameters， namely reinforcement ratio and slenderness ratio. were investigated. The effects of reinforcement ratio and slenderness ratio on the failure mode and bearing capacity of reinforced single-limb angle components were analyzed， and the reinforcement mechanism of the GRPU non-destructive reinforcement scheme was revealed. The results showed that the reinforcement limited the torsional deformation of the components and improved their bending stiffness， thereby enhancing the bearing capacity of the members； with the increase of the slenderness ratio and reinforcement ratio， the reinforcement effect continued to improve. Finally， a reinforcement ratio for single-limb angles was proposed.