Large-format façade elements with hardwood structure and focus on sustainability goals in the construction industry - development and characterization of the textile-concrete-wood composite construction
In cooperation with the industrial partner (EudurBau) and two other TU Dortmund University chairs (Building Materials, Solid Construction), large-format façade elements made of textile-reinforced concrete cover layers and an internal timber structure are being developed. The component can thus transfer both vertical and horizontal loads in its plane, providing both a supporting and stiffening function. The thickness of the surface layers is reduced to the required minimum to save material and weight, which is achieved by using non-metallic reinforcement as fabric instead of classic steel reinforcement. A shear-resistant, yet detachable for recycling, connection is to be developed between the timber structure and the surface layer. The resulting robustness of the façade element should enable dimensions of up to 12 m in length and 3.5 m in height. Compared to previous solutions, these large-format elements reduce gray emissions, transport and installation costs as well as the number of joints, with benefits in terms of durability and appearance.
Concrete façade elements have numerous advantages in terms of durability, load-bearing capacity and availability. Due to their surface quality and price-performance ratio, they continue to have a high market relevance for building construction, but contribute significantly to gray emissions during the construction of buildings. Therefore, such elements in building construction can and should be improved with regard to sustainability criteria. According to DIN EN 15643, improvement criteria are defined using three pillars - environmental, social and economic. Taking these three pillars into account, large-format façade elements are to be developed and brought to market maturity.
The reduction of gray emissions for concrete façade elements can be achieved through the targeted reduction of the concrete volume to thin surface layers, as the mineral properties are particularly advantageous there. On the one hand, this relates to resistance to mechanical impacts and other environmental influences such as moisture, fire, noise, cold, heat, etc. The embedding of the wood structure within the façade element should be durable under the protection of the mineral cover layers, even without the use of wood preservatives, as wood-decomposing organisms are denied both access and moisture. The CO2 bound in the wood structure is thus permanently bound and results in an improved balance of gray emissions of the component in the life cycle and beyond.
The following images show a proof of concept that was investigated as part of a student's final thesis. Some of the ideas from this thesis will be incorporated into the research project.
