Experimental and Numerical Study of Moisture-induced Stress Formation in Hexagonal Glulam Using X-ray Computed Tomography and Finite-element AnalysisShow others and affiliations
2018 (English)In: BioResources, E-ISSN 1930-2126, Vol. 13, no 4, p. 7395-7403Article in journal (Refereed) Published
Abstract [en]
Hexagonal glue-laminated timber with large cross-sections, made from small diameter logs, was studied. Effects of relative humidity variations on the moisture-induced stresses were investigated to evaluate how the prediction model compared to a real outcome. The test samples were exposed to an environment with relative humidity variations from 80% to 30%. The moisture content inside the samples was measured via X-ray computed tomography scanning. A moisture transport and a hygromechanical finite element simulation model was used for the prediction of moisture content and resulting stress distribution. The results from both the test and simulation showed that the moisture content in the edge angles of the samples dropped rapidly due to a large moisture diffusion rate. The moisture gradient was generated via a different moisture transfer rate at the inner and external parts of the samples. The maximum stress perpendicular to the grain in the simulation was 8 MPa and was located at the surface near the corners. This stress peak caused cracking according to the model, which was also seen in the test samples. The results for the measured moisture content agreed with the simulated results and this indicated that the moisture transfer model was adequate for simulation.
Place, publisher, year, edition, pages
University of North Carolina Press, 2018. Vol. 13, no 4, p. 7395-7403
Keywords [en]
Glulam, X-ray computed tomography, Finite element model, Climate variations, Moisture-induced stress
National Category
Other Mechanical Engineering
Research subject
Wood Science and Engineering
Identifiers
URN: urn:nbn:se:ltu:diva-70605DOI: 10.15376/biores.13.4.7395-7403ISI: 000454215100018Scopus ID: 2-s2.0-85069949572OAI: oai:DiVA.org:ltu-70605DiVA, id: diva2:1242091
Note
Validerad;2018;Nivå 2;2018-08-27 (andbra)
2018-08-272018-08-272024-07-04Bibliographically approved