Moisture induced stresses in cross laminated timers (CLT) made from hydrothermally modified fir wood

Document Type : Research Paper

Authors

1 Teacher

2 Department of Wood and Paper Sciences, Tarbiat Modares University, P.O. Box: 356-46414, Noor, Mazandaran, Iran

10.22034/ijwp.2023.560626.1565

Abstract

Cross-Laminated-Timbers (CLT) absorb/desorb moisture from surrounding atmosphere when exposed to wet/dry conditions; such all engineering massive wood-based products. The moisture gradient occurs due to this process, which is responsible for moisture induced stresses. In the current research work, the moisture induced stresses due to the moisture gradient have been studied in the CLT. The sample panels were made with 5-plys. One and two plys of hydrothermally treated wood at 150°C were placed on both sides as surface layers. Afterwards, the sample panels were exposed to wet to dry cycles (RH of 88 to 32%) and dry to wet cycles (RH of 32 to 88%). Results revealed that the moisture gradient as well as the moisture induced stresses are reduced due to application of the hydrothermally treated laminations on both side of the panels in comparison with control samples.

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References

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Iranian Journal of Wood and Paper Industries
Volume 13, Issue 4
March 2023
Pages 497-507

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