Abstract
Laminated veneer lumber (LVL) is an important engineered wood product. Internal structural changes have a substantial influence on the mechanical performance of LVL. To investigate the relationship between the internal structural changes and the compressive strength, poplar LVL layering is manufactured by taking into account the veneer lathe checks, namely lathe checks both facing inwards (TLLT), lathe checks both oriented outwards (LTTL) and lathe checks in one layer facing outwards (LTLT). Macroscopic compressive strength of the samples is measured using a universal testing machine. Microscopic internal structural changes are periodically recorded with X-ray CT when the samples are compressed using a load cell. The results show that the compressive strength of LTLT is significantly higher than that of LTTL and TLLT types of LVL. During the compression test, density increase in the samples is non-homogenous. There is a minor increase in density of the glue line, while this is larger in regions with a low density. Density increase is mainly induced by collapse of large vessels. However, the presence of phenol formaldehyde resin can enhance the resistance of vessels against collapse. Structural changes, i.e., vessels collapse and collapse propagation, are likely to occur in locally heterogeneous regions. Propagation of collapsed vessels is more frequently observed in regions where large vessels are contiguous.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.