TİMUÇİN BARDAK, SELAHATTİN BARDAK, ESER SÖZEN

Masif odun ve kontrplakların eğilme testinde gerinim dağılımlarının dijital görüntü korelasyonu ile belirlenmesi

ÖzetÇalışmanın amacı: Bu çalışmada, kayın (Fagus orientalis L.), meşe (Quecus robur) ve kayın kaplamalardan elde edilen kontrplakların eğilme testinde yer değiştirme ve gerinim alanları dijital görüntü korelasyonu yöntemiyle karşılaştırılması amaçlanmıştır.Materyal ve Yöntem: Ahşap malzeme olarak kayın (Fagus orientalis L.), meşe (Quercus robur) ve kayın kaplamalardan elde edilen kontrplaklar kullanılmıştır. Daha sonra, test numunelerinin yoğunlukları ve eğilme dirençleri hesaplanmıştır. Dijital görüntü korelasyon analizi, bir numunenin yüzeydeki yer değiştirmeyi çözmek için kullanıldı. Malzemenin deformasyonu numune yüzeyindeki işaretlerin yer değiştirmesini izleyerek elde edilebilir.Sonuçlar: Yapılan çalışmalar sonucu en yüksek statik eğilme direnci kayın malzemede, en düşük ise kontrplakda bulunmuştur. Dijital görüntü korelasyon analizi masif malzeme ve kontrplak da eğilme davranışını anlamamıza yardımcı olan gerilme ve yer değiştirmenin tespitinde etkili bir tekniktir. Araştırma vurguları: Bu araştırmanın sonuçları, Dijital görüntü korelasyonu tekniğinin farklı odun kompleks yapılarındaki tam alan deformasyonlarını ölçebildiğini göstermektedir. Ahşap mühendisliği alanında sınırlı DIC çalışması nedeniyle gelecekte daha kapsamlı çalışmalara ihtiyaç vardır.

Anahtar Kelimeler:

Gerinim dağılımı, Masif odun, Kontrplak, Görüntü analizi

Determination of Strain Distributions of Solid Wood and Plywood in Bending test by Digital Image Correlation

Abstract Aim of study: In this study, it is aimed to compare displacement and strain fields of the plywood obtained from fagus coverings, oak (Quecus robur) and beech (Fagus orientalis L.) by digital image correlation method.Material and Methods: As wood material, beech (Fagus orientalis L.), oak (Quecus robur) and plywood obtained from fagus veneers were used. Then the densities and modulus of ruptures of the test specimens were calculated. Digital Image Correlation Analysis (DIC) was developed to resolve the displacement on the surface of a specimen. Deformation of the material can be achieved by tracking the displacement of markers on the sample surface.Main results: The results of the studies were found to be the highest static bending strenght in beech material and the lowest in plywood. The DIC technique is effective in detecting the displacement and strain, which helps to understand the bending behavior of solid wood and plywood Research highlights: The results from this research indicate that the DIC technique is capable of measuring full-field deformations in different wood complex structures. Due to limited DIC study in the field of wood engineering, there is a need for more extensive work in the future

Keywords:

Stress distribution, Solid wood, Plywood, image analysis,

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