LCT – LifeCycle Tower Construction system independent of location
Result of a research project for a prefabricated wood-concrete composite structure above the height from which a building is 'high-rise’
merz kley partner, Dornbirn
In most countries, the permitted height of timber buildings is still restricted by law. Despite great advances in research into fire protection, three to six storeys remain the maximum, and onlya few countries, such as England and Norway, allow buildings above eight storeys – the height from which a building is ‘high-rise’ – to be constructed out of the combustible building material wood. The development of a construction system with up to twenty storeys was the theme of the research project LifeCycle Tower. The project examined an exemplary building on a ‘footprint’of 25 x 38 metres in which eighteen timber-built floors rest on two plinth storeys constructed from mineral-based materials.The concrete core with two staircases, lifts and a fire-fighting lift takes the horizontal loads from the prefabricated, composite timber-concrete floor slabs. These elements rest on exposed, glue-laminated timber columns positioned on a 2.70-metre grid that are integrated into the facade elements. Prefabricated service elementswith integrated heating, cooling, sprinklers, and in some cases also lighting – elements that also meet the acoustic requirements– are hung between the visible timber ribs. It was possible to prove that the capacity of the construction material is adequatein structural terms and that, compared with conventional construction methods, the use of resources as well as the primary energy consumption can be considerably reduced. It was also possible to demonstrate that the possibilities offered by prefabricationallow a reduction of the construction period by one-third. The flexibility of use together with the separation of load-bearingstructure, envelope, building services and interior finishing ensure a long life for the building – an important parameter for sustainability. Special fire protection measures meet the required safety standards. That it is also possible to meet the economic requirements will be shown by the eight-storey prototype, which it is due to be completed in Dornbirn in the winter of 2011.