Strength and stiffness of adhesively bonded timber-steel composite beams

As a sustainable building material, timber can help replace conventional CO2-intensive construction materials. To further establish timber structures in the sector of e.g. office buildings, appropriate cross-sections for large spans are required. These could be realized as composite cross-sections consisting of different materials. The materials timber and steel can complement each other in composite cross-sections and compensate for the weaknesses of the other bonding partner. Advantages include the use of slender steel profiles, as they are embedded in the timber and local stability failure is prevented. Also, the fire resistance is increased by the embedment in the timber. Finally, the composite beams allow for typical bolted steel connections with high load-carrying capacity and stiffness, as is usual in steel construction.
The results demonstrate the high potential of timber-steel composite beams. The geometry combination can be chosen accordingly to the governing loading mode. While the horizontal combination is ideal for structures subjected to bending loads (deflection), the vertical combination is ideal for components subjected to high shear loads. ... mehrThe tests have also shown that slender steel profiles, at risk of stability failure, can be used. The small deviations of test results to analytical results, however, only apply to the analysed geometry combinations. Therefore, in further numerical and experimental investigations, other material and geometry combinations must be investigated, in order to determine e.g. geometrical boundary conditions for the use of the analytical equations.