UniStrand: next generation structural wood materials

In recent years, timber constructions have been able to demonstrate their suitability for multi-storey construction through various lighthouse projects (e.g. LCT ONE, HoHo etc.). The use of wood as structural material in the construction sector is not only favourable to substitute energy-intensive raw materials while storing carbon simultaneously, but also for the need to satisfy the increased demand for building materials. A dramatic increase in the utilization of the resources used is just as inevitable as the digital dimensioning of building components. Currently successful timber construction products such as cross laminated timber are predominantly based on softwood lumber and have a low raw material yield (30-40%) due to the process. The "UniStrand" project is intended to outline and research the technological and design fundamentals for a (approx. 7-15cm) thick, panel-shaped timber building material for multi-storey, structural building applications. The starting material will be wood strands, which can be produced with a high raw material yield of over 80%. Hardwood and softwood assortments or a combination thereof are to serve as raw material. By forming unidirectionally oriented boards of different densities, a predictable intermediate product with improved mechanical properties compared to already established strand-based products (OSB, LSL) is to be created. Finally, the required barrier effect and material thickness of the layered wall and ceiling elements will be achieved by crosswise ply bonding. Based on the design optimization of the finished elements, coupled with an application-oriented cut optimization, it is possible to produce targeted elements that use high-performance panel material only where this is also statically required. The results are evaluated in parallel by a process-oriented life-cycle and technology assessment. The fundamentals created form the basis for large-scale industrial implementation and pave the way for a resource-efficient, next generation wood building material.