When designers started using fiber-reinforced polymers (FRP) for structural retrofits over 20 years ago, they had only full-scale structural testing to justify their designs. As codes and guidelines have become more widely available, however, we’ve observed that designers have become more reliant on the use of empirical equations and less reliant on basic mechanics and structural proof testing. Because empirical equations may not be appropriate for a specific application, however, designs based on these equations may not achieve the desired performance targets.
We’ve also noted that designers may not be aware of some of the critical issues necessary for proper installation of FRP systems. These systems can’t be installed successfully without careful attention to existing conditions, service requirements, material properties, and application details.