Kızılçamdan (Pinus brutia Ten.) Üretilen Tabakalı Kerestede Cam Lifi ve Çelik Plaka ile Güçlendirmenin Eğilme Performansına Etkisi

Bu çalışmada kızılçam kullanılarak üretilmiş ve cam lifi ve çelik plaka ile güçlendirilmiş tabakalı kerestelerin eğilmedeki performans özellikleri araştırılmıştır. Tabakalı kerestede eğilme özelliklerini iyileştirmek için lokal güçlendirme yapılmıştır. Çalışmada kızılçam kerestesi kullanılarak 15 adet 10 x 200 x 3000 mm ölçülerinde tabakalı kereste örnekleri üretilmiştir. Bütün örneklerin en alt katmanı parmak dişle birleştirilmiş iki keresteden; üstündeki katman tek parça keresteden; orta ve üstü katman parmak dişle birleştirilmiş altı elemandan ve en üst katman ise tek elemandan oluşmaktadır. Dolayısıyla kontrol örneklerinde kırılmaların en alt tabakada parmak dişli birleştirmede olması planlanmıştır. Güçlendirme işlemi cam lifi ve çelik plaka kullanılarak gerçekleştirilmiştir. Tabakalı kereste örneklerinin üç nokta eğilme testi ile performans özellikleri belirlenmiştir. Çalışma sonuçlarına göre kızılçam kullanılarak üretilmiş tabakalı kerestelerde elastikiyet modülü cam lifi ile % 14, çelik plaka ile % 24 artmıştır. Cam lifi maksimum yük taşıma kapasitesini% 27, çelik plaka ise % 36 arttırmıştır. Güçlendirme tabakalı kirişlerde kırılma modunu da değiştirmiştir.

Anahtar Kelimeler:

Kızılçam, Tabakalı kereste, Güçlendirme, Cam lifi, Çelik plaka

Effects of Fiberglass and Steel Sheet Reinforcement on the Bending Performance of Glulam Beams Constructed with Turkish Red Pine (Pinus brutia Ten.)

A study was conducted to investigate the bending performance of glulam beams constructed of Red pine reinforced by fiberglass and steel plates. Local reinforcement is proposed in order to improve the flexural strength and stiffness of glulam beams. For the study, 15 full size glulam beams constructed of Turkish red pine lumber were produced. All beams had similar 5 layers consisting of two finger-jointedmembers at the bottom, a single member at the fourth, six finger-jointed-members at the third and second layer and another single member at the top. Glulam beams were tested using three-point bending test to determine their load-deformation behavior. According to test results, elasticity of the glulam beams can be improved 14% and 24% using fiber glass and steel plates. Similarly, maximum load carrying capacity of glulam beams constructed of Turkish red pine lumbers may be improved 27 % and 36 % by using fiberglass and steel reinforcements, respectively. Reinforcement also changed the failure mode of glulam beams tested

Keywords:

Glulam, Turkish red pine, Reinforcement, Fiberglass, Steel plate,

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