Fundamentals and recent strength results of connections in modern hardwood timber structures

Hardwood is becoming more in focus and more important in timber structures. The natural higher strength increases the potential of timber structures and power to compete with steel or concrete. However, for designing connections, the performance parameters stiffness and load-carrying capacity based on, e.g. embedment strength or withdrawal capacity need to be known but these are less standardized compared to softwood. Since not all types of connections are relevant to be used as high-performing connections in hardwood, structural systems, parameters of connections are summarized and discussed with a focus on relevance for their use in hardwood. For the connection types with glued-in rods and steel dowels, the assembling procedure, the load-carrying capacity and failure behaviour is investigated in relation to the necessary design parameters as a first part of the relevant connections. First, the results of their design and influencing parameters are presented, summarized and compared regarding current design equations.