Novel 3D FRP system used for more effectively and readily strengthening of precast concrete elements

Abstract

The burgeoning precast concrete market necessitates innovative strengthening solutions to ensure the durability and safety of precast elements. This study presents a 3D Fiber Reinforced Polymer (FRP) system designed to reinforce precast concrete elements, providing a more effective and efficient method compared to traditional Externally Bonded (EB) and Near Surface Mounted (NSM) FRP techniques. The system utilizes extended FRP strips that function as bent anchorages, U-wraps for anchorage protection, and additional FRP patches to prevent anchorage cutoff at bent corners. A comprehensive experimental campaign involving 33 specimens assessed the system's performance, demonstrating significant improvements in flexural and shear capacities with minimal surface preparation requirements. The experiments included varying strip widths and anchorage configurations to optimize the system's effectiveness. Numerical models were developed to simulate the flexural behavior of the 3D FRP reinforced elements, accurately predicting load-deflection responses and failure modes. Both experimental and numerical results suggest that the 3D FRP system not only enhances the load capacity and structural integrity of precast concrete elements but also simplifies the installation process, offering a promising solution for the construction industry. The findings also offer practical guidelines for the design and fabrication of 3D FRP reinforced concrete elements, contributing to a more sustainable and economical construction approach.