Experimental determination of the combined loading behaviour of scaled timber frame walls subjected to bending and shear

Abstract

The shift towards using more and higher timber structures comes with more questions regarding their structural behaviour. For instance, structural robustness and racking resistance are two important themes currently being researched more thoroughly. Within the context of structural robustness, timber walls could become self-supporting due to damage occurring to the underlying supporting elements. In such a scenario, timber walls are subjected to in-plane bending and possibly horizontal (shear) loads, a combination of load cases for which little knowledge has been developed in the context of timber frame construction. Therefore, an experimental and numerical campaign is presented in which six timber frame walls were tested. Two walls were loaded solely under in-plane horizontal loads until failure, and four walls were subjected to a combination of in-plane vertical (bending) and horizontal loads. Results showed that increasing the vertical loading lowered the horizontal load (or racking) resistance of the timber frame wall. The interaction behavior was also visible in the load-displacement diagram, which depicted a faster decrease in stiffness in the elastoplastic and plastic area of the wall and decreased yielding force whenever more vertical loading was applied. This interaction behavior was similar to the predictions according to mesoscale finite element models.