Structural Enhancement of Framing Members Using Polyurea

This paper demonstrates the potential for using field applied structural coatings to reinforce traditional framing members and standard building ties, thereby providing an improved and continuous foundation to roof load pathway. Tension tests are performed on rafter top plate model joint connections, some of which were reinforced with a hurricane tie, to establish how much of a difference a polyurea coating made as the joints between the stud and top plate, and top plate and rafter, were loaded to failure. Polyurea provides universal strengthening compared to hurricane ties with the added advantage that members and joints can be protected from a multitude of threats including corrosion due to moisture, damage due to flood; and, with selfextinguishing properties, fire. Results show that the failure mode of the structures tested can be controlled by using different types of field or factory applied polymer coatings. The addition of the coating allowed both unreinforced and reinforced configurations to withstand higher loads (200-400% more). In general, the polyurea delayed the onset of failure and significantly strengthened every configuration by increasing the amount of work/energy required to pull it apart; in some cases, by almost 800%.