Budapest University of Technology and EconomicsFaculty of Civil Engineering - Since 1782

In search for a solution of a sustainable construction with less impact on environment while maintaining a sufficient structural performance, cross laminated timber and concrete composite slabs/beams have been increasingly proposed for medium-to-large span structures. Not only that the composite solution is stiffer and stronger than a timber equivalent, it is also associated with a substantially lower greenhouse gas emission. The advantages are so convincing that an increasing number of buildings are constructed adopting this technology, but because of the uncertainties and unknowns with a considerable premium.

The connection between the two materials is achieved in various ways. The most common are screw dowels, glued perforated plates and notches in the timber creating a concrete to timber bearing interface. Research has already been done towards creating a two-way spanning slabs by attaching the timber panels in the normally non-loadbearing direction. The performance of the system both in terms of stiffness and capacity, let alone the construction costs, depends largely on the method and layout of the connectors.

In this proposal the performance of various connection types shall be investigated by models, testing or a thorough investigation of literature in order to determine the base parameters for an optimization procedure. The objective of the research is to investigate the optimal layout and type of connectors to achieve an admissible, but minimum cost or a maximum achievable performance design.

The design parameters can be the type of connector and its dimensions, composition and the positions of the connectors. The dimensions and composition of the connectors can be handled separately adopting mesoscale FE models benchmarked to test available in literature. The relevant parameters (e.g. stiffness and capacity) obtained for the connectors can be used in a global analysis of building components e.g. flat slabs, ribbed slabs and other common structural types. Optionally the research can be extended to two-way spanning and indeterminate structures.