Some mechanical properties of plywood produced from eucalyptus, beech, and poplar veneer

Abstract

In this study, we determined the flexural properties and tensile shear strength of five-ply plywood panels produced with eucalyptus (Eucalyptus grandis), beech (Fagus orientalis), and hybrid poplar (Populus x euramericana) using urea-formaldehyde (UF), melamine-urea-formaldehyde (MUF) and phenol-formaldehyde (PF) adhesives. Flexural properties were tested on both parallel and perpendicular to grain samples. Tensile shear-strength tests were conducted on four glue lines of the plywood panels, and the effects of species of trees, type of adhesives, and direction of load were determined. The results of variance analyses showed that the effects of species of trees, direction of load, and type of adhesive on flexural properties were significant, but it was determined by specific flexural properties that the effect of the type of adhesive was based on the density of the plywood. In addition, as a result of findings, it can be said that specific mechanical properties may be a good predictor for comparative studies.

Some technological properties of laminated veneer lumber produced with fast-growing Poplar and Eucalyptus

“…It is well known that the greater the veneer density is, the greater the tensile shear strength is. Similar results were reported by other researhers (Özen 1981, Örs et al 2002, Hashim et al 2011, Bal and Bektaş 2014. Group B was not tested for shear strength.…”

Ligneous resole adhesives for exterior-grade plywood

“…4. It is apparent that the absolute values for both MOR as well as MOE are relatively high which is mainly due to the high density of the chosen hardwood species beech (Green et al 2010;Cihad Bal and Bektas 2014). Even though the values should be treated with care due to the limited number of specimens tested per fibre direction and adhesive (n = 2), the observed bending behaviour was quite similar for all plywood boards bonded with the different resins, as failure again occurred predominantly in the wood veneers and not in the glue lines.…”

Mechanical Properties of Plywood From Batai (Paraserianthes Falcataria), Eucalyptus (Eucalyptus Pellita) and Kelempayan (Neolamarckia Cadamba) With Different Layer and Species Arrangement

“…The KB and KE arrangements were not significantly different at parallel bending because the strength was highly contributed by kelempayan. Flexural properties of veneer parallel to the grain direction is better than perpendicular (Bal & Bektas 2014). Plywood with KE arrangement had significantly higher property than K arrangement because the KE had a higher density of veneer (eucalyptus) which supported strength.…”

“…Furthermore, the thin face and back veneers (1.0 mm) used in construction, likely gave low strength to the parallel bending. On the other hand, Bal & Bektas (2014) produced 5-layer plywood with parallel strength higher than perpendicular. The parallel board had veneers parallel to board length with total thickness of 9 mm compared to perpendicular board with thickness of 6 mm.…”