Carbon Fiber and Structural Timber Composites for Engineering and Construction

There are environmental and potential economic advantages in using laminated veneer lumber (LVL) for building structures, but load-carrying capacity constrains uptake. Building on previous work in the field, the authors test the strategic placement of carbon fiber-reinforced polymer (CFRP) to improve the flexural strength of timber beams, investigating both positive and negative bending moments of structural assembly. The results demonstrate: unidirectional CFRP applied as a U-wrap on the tension side of beams improves load carrying by 25%, stiffness by 20%, and ductility by 30%; a combination of uni- and bidirectional CFRP mesh applied to beam-column joints with no other connectors achieves substantial structural continuity between beams. U-wrap reinforcement also shifts the mode of failure from abrupt to gradual. Another significant observation is that wood splinters appear to cause premature failure, and we consider solutions to this issue. Discussion of the outcomes for advancing the uptake of timber as a more sustainable structural material are undertaken, along with an outline of further work