LIU Xiaoling,XUAN Shiqing,PAN Licheng,et al.Effects of Veneer Hole Repair Methods on Mechanical Properties of Plywood[J].Chinese Journal of Wood Science and Technology,2026,40(01):82-89. DOI: 10.12326/j.2096-9694.2025101.
To investigate the effects of veneer hole-repair methods on the mechanical properties of plywood
rotary-cut
Eucalyptus
veneers with circular holes were used as material. Three repair methods
namely veneer patch
calcium hydroxide-based putty and wood-mixed putty
were applied to the holes before plywood manufacture. A non-contact full-field strain measurement system (digital image correlation
DIC) was used to analyze strain transfer during the bonding strength test. The results showed that pronounced local strain concentration occurred around unrepaired holes
disrupting the strain-transfer path. Compared with the control group without holes
the bonding strength
modulus of rupture (MOR)
and modulus of elasticity (MOE) of the group with holes unrepaired decreased by 32.92%
18.78%
and 10.65% respectively. Plywood prepared from veneers repaired with calcium hydroxide-based putty (Group CP) and wood-mixed putty (Group WP) exhibited simi
lar strain-evolution patterns during the bonding strength test. These repair materials effectively filled the holes and improved stress transfer. Compared with the unrepaired group
the bonding strength increased by 43.52% and 39.81%
respectively
while the MOR and MOE increased by 18.62% and 10.96% for Group CP and by 14.72% and 7.20% for Group WP
respectively. Although veneer patch repair improved the mechanical properties of plywood to some extent
gaps remained at the hole edges
resulting in insufficient bonding with the veneer substrate and a limited repair effect. Overall
the two putty-based repair methods showed better performance in improving the mechanical properties of plywood
providing a useful reference for the repair of veneer hole defects in plywood production.
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