Abstract
Moisture-induced stresses resulting from climate variations of the environment can induce cracks in timber members and thus affect the safety and serviceability. The present study highlights—by means of numerical simulations—the distribution and development over time of moisture-induced stresses in various glulam cross sections during wetting. The results show that local stresses may be significantly larger than average stresses, the extent of which strongly depends on the geometrical configuration of the glulam laminates. Suggestions are made on the design of glulam cross sections to minimize the arising local stresses. Furthermore, the studied wetting exposure results in local tensile stresses that exceed the tensile strength of the material. In smaller cross sections, this is the case within few days, while more time is required in wider cross sections.
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Acknowledgments
The authors acknowledge the support of the work from Norwegian Timber Industry, Norwegian Road Authorities and Christiania Spigerverk AS and Norwegian Research Council under KMB project grant 186821/I10. Specimens are delivered by Moelven Limtre AS and personal communication regarding production issues is highly acknowledged.
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The authors declare that they have no conflict of interest.
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Angst, V., Malo, K.A. Moisture-induced stresses in glulam cross sections during wetting exposures. Wood Sci Technol 47, 227–241 (2013). https://doi.org/10.1007/s00226-012-0493-8
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DOI: https://doi.org/10.1007/s00226-012-0493-8