Abstract
The study concerns the question of how the shape stability features of laminated columns of Norway spruce can be improved in terms of twist through optimal orientation of the individual laminates. Both experimental testing and numerical simulations were employed for evaluating twist stability. In all the columns studied, deformations were measured experimentally at different moisture content levels. A number of columns were also selected for numerical analysis in order to obtain a more thorough understanding of the twist behavior involved, their geometries and material properties of interest being determined. The experimental results showed the twist stability of the columns to be highly dependant upon the internal orientation of the individual laminates. It was also found that high quality columns in terms of shape stability could be manufactured, even when the center-core material has a strong twist tendency. The numerical simulations performed were in close agreement with the experimental results.
Zusammenfassung
Diese Studie befasst sich mit der Frage, wie die Verdrehung von Kreuzholzbalken aus Fichte durch optimale Anordnung der zu verklebenden Teile reduziert und dadurch die Formstabilität der Balken verbessert werden kann. Die Formstabilität der Balken wurde sowohl experimentell als auch mit Simulationsrechnungen untersucht. Bei allen untersuchten Balken wurden Verformungen bei unterschiedlichen Holzfeuchten experimentell gemessen. Um das Verdrehungsverhalten besser zu verstehen, wurde dieses bei einigen Balken rechnerisch untersucht. Dazu wurde deren Aufbau und die relevanten Materialeigenschaften bestimmt.
Die Versuchsergebnisse belegten die grosse Abhängigkeit der Formstabilität von der Anordnung der Einzelteile. Ausserdem zeigte sich, dass hochwertige formstabile Balken auch aus marknahem Holz mit starkem Drehwuchs hergestellt werden können. Die rechnerische Simulation stimmte mit den Versuchsergebnissen sehr gut überein.
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Eriksson, J., Ormarsson, S. & Petersson, H. An experimental and numerical study of shape stability in laminated timber columns. Holz Roh Werkst 63, 423–429 (2005). https://doi.org/10.1007/s00107-005-0058-8
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DOI: https://doi.org/10.1007/s00107-005-0058-8