Study of Stress Capacity Improvement of L-type Joint by Chemical Modification of Wood

Hamideh Abdolzadeh, Mohammad Layeghi, Ghanbar Ebrahimi, Mehdi Ghassemie

Abstract


Chemical modification of wood with the aim of improving its dimensional stability can also influence the mechanical behavior of the timber when assembled into a structure. Hence, in this study, the stress-carrying capacity of mitred and butted L-type joints constructed from furfurylated wood samples with two weight percentage gains (WPGs), i.e., 20 and 60% (low and high levels, respectively), was investigated by subjecting the specimen to a diagonal tension load. Results indicated that the bending moment resistance of both L-type joints depends on the WPG. The L-type joints’ bonded stress value with poly-vinyl acetate (PVAc) adhesive decreased with increasing WPGs. Likewise, in the case where epoxy adhesive was used for jointing, the stress capacity increased for both joints constructed with furfurylated wood. Values of tension stress in the butted joint were higher compared to the mitred one. Evaluation of shear stress parallel (τ׀׀) and perpendicular (τ┴) to the grain of members jointed with PVAc adhesive demonstrated that the shear stress-carrying capacity decreases as furfurylation level increases. However, by applying epoxy adhesive for jointing, τ׀׀ and τ┴ were increased by raising the furfurylation levels.

Keywords


Furfurylation; Stress capacity; Dowel; L-type joint

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Welcome to BioResources! This online, peer-reviewed journal is devoted to the science and engineering of biomaterials and chemicals from lignocellulosic sources for new end uses and new capabilities. The editors of BioResources would be very happy to assist you during the process of submitting or reviewing articles. Please note that logging in is required in order to submit or review articles. Martin A. Hubbe, (919) 513-3022, hubbe@ncsu.edu; Lucian A. Lucia, (919) 515-7707, lucian.lucia@gmail.com URLs: bioresourcesjournal.com; http://ncsu.edu/bioresources ISSN: 1930-2126