Kayın odununda statik ile dinamik elastikiyet modülü arasındaki ilişkinin belirlenmesi

Bu çalışmada, tahribatsız test yöntemlerinden birisi olan stres dalga yöntemi kullanılarak belirlenen dinamik elastikiyet modülü ile TS ISO 13061-2 (2021) standardına göre belirlenen statik elastikiyet modülü arasındaki ilişki incelenmiştir. Bu kapsamda rastgele seçilmiş 12x13x110 cm3 boyutlarındaki kayın (Fagus orientalis Lipsky) keresteler kullanılmıştır. Kerestelerin radyal ve boyuna yöndeki uçuş süreleri, 1 μs hassasiyetteki FAKOPP marka mikro saniye zamanlayıcı kullanılarak belirlenmiştir. Kayın kerestelerin tam kuru yoğunlukları TS ISO 13061-2 (2021) standardına göre belirlenmiştir. Elde edilen veriler ile öncelikle stres dalga hızı ve daha sonra dinamik elastikiyet modülü değerleri hesaplanmıştır. Kayın keresteler daha sonra statik elastikiyet modülü testlerinin yürütülebilmesi için 20x20x320 mm boyutlarına getirilmiştir. Numunelerin statik elastikiyet modülü direnci testleri Shimadzu AGIC/20/50KN üniversal test cihazında TS ISO 13061-4 (2021) standardına göre gerçekleştirilmiştir. Statik ve dinamik elastikiyet modülü sonuçlarının lineer regresyon analizleri yapılmıştır. Analiz sonuçlarına göre statik ve dinamik elastikiyet modülü arasında güçlü bir ilişki olduğu tespit edilmiştir.

Anahtar Kelimeler:

Tahribatsız test teknikleri, Stres dalgası, Kayın, Elastikiyet modülü, Mikrosaniye zamanlayıcı

Determination of the relationship between static and dynamic modulus of elasticity in beech wood

In this study, the relationship between the dynamic modulus of elasticity determined using the stress wave method, which is one of the non-destructive test methods, and the static modulus of elasticity determined according to the TS ISO 13061-2 (2021) standard was investigated. In this context, randomly selected beech (Fagus orientalis Lipsky) timbers of 12x13x110 cm3 in dimensions were used. The time of flight of the timber in the radial and longitudinal directions was determined by using a FAKOPP microsecond timer with an accuracy of 1 μs. Oven-dry densities of the beech timbers were determined according to the TS ISO 13061-2 (2021) standard. Firstly, stress wave velocity and then dynamic modulus of elasticity values were calculated with the obtained data. The beech timbers were then cut into 20x20x320 mm dimensions for the static modulus of elasticity tests. Static modulus of elasticity resistance tests of the specimens were carried out in a Shimadzu AGIC/20/50KN universal test machine according to the TS ISO 13061-4 (2021) standard. Linear regression analyses of static and dynamic modulus of elasticity results were performed. According to the results of the analyses, it was determined that there is a strong relationship between the static and dynamic modulus of elasticity.

Keywords:

Non-destructive tests, Stress-wave, Beech, Modulus of elasticity,

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