Fire resistance of novel hybrid components

Timber is a popular building material whose use has been steadily increasing in recent years. The advantages of timber as a building material in terms of resource efficiency and its ability to store CO2 as well as the low mass and comparatively short construction times of timber constructions mean that timber construction is becoming increasingly important. In addition to the undoubted advantages of timber construction, there are also some disadvantages compared to other construction methods. Timber components have a lower load-bearing capacity and stiffness than components made of concrete or steel. Although high fire resistance durations can be achieved with timber components with the appropriate dimensions, the building material is combustible. One way of exploiting the advantages of the respective building materials and compensating for possible disadvantages is to use so-called hybrid components, in which the components of the different building materials are connected to each other in a shear-resistant manner. With hybrid construction methods, building materials can be used as required, usage limits can be extended and resource and energy savings can be realized. It therefore makes sense to combine the advantages of timber as a building material in terms of resource efficiency, its low weight and its ability to store CO2 with the advantages of other building materials, e. g. in terms of strength and stiffness, in order to develop high-performance and sustainable components.
The contribution will demonstrate the development of innovative hybrid components in timber-concrete and steel-timber composite construction with a focus on fire resistance behavior. In addition to its load-bearing function, the timber also acts as a fire protection material which, due to its low thermal conductivity and slow burning, protects the composite joint and can prevent rapid heating of the steel or spalling of the concrete. A further focus is on the design of the bond between the two building materials, for which new types of joints are used for reasons of sustainability and were investigated with regard to the influence of high temperature exposure.