Glued joints in hardwood timber

The use of glued joints offers an option with ample aesthetic and functional possibilities in the design of wood structures. This type of joint is used since years 1970 in countries of North and Central Europe, for the design and construction of glulam (glued laminated timber) structures. This has led to diverse investigations in the experimental analysis of joints made with steel bars glued-in glulam subjected to axial loads. It led to diverse formulae of empirical base for the design of the same ones. Of these empirical formulae, the proposal of Riberholt is considered to be a pioneer. Likewise, the Eurocode 5 has included in more recent years a formula for the design of these unions, though only as an Informative Annex.From these precedents, our research equipment has developed an extensive experimental campaign directed to evaluating the adjustment of these proposals to the design of joints in elements made with hardwood saw timber. This can be of great usefulness in works of restoration, because glued joints have an enormous potential for repairing old structures.In this paper, diverse experimental campaigns made with threaded steel bars glued-in hardwood saw timber of high density are described.