Lifli polimer levhaların betona bağlanmasında fan tipi ankrajların araştırılması
Yükleniyor...
Dosyalar
Tarih
2024
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Aksaray Üniversitesi Fen Bilimleri Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Betonarme yapılarda CFRP şeritler, onarım/güçlendirme veya kapasite artırımı gibi sebeplerden dolayı sıkça kullanılmaktadır. CFRP levhaların uç bölgelerinde keskin dönüşler olmaktadır. Yapılan çalışmalarda levha ucundaki kullanılan ankrajın başarısının uygulamanın başarısı anlamına geldiği belirtilmiştir. Bu çalışmalarda betonu 10 MPa basınç dayanımında olan, betonarme kiriş elemanlarının çekme bölgesine CFRP levha yapıştırılmış ve uç bölgesinde fan ankraj uygulaması araştırılmıştır. Çalışmanın değişkenleri; levha genişliği, fan ankraj adedi ve levha ucunda ilave bir katmanın kullanılmasıdır. Deneysel çalışmada 100 mm genişliğinde CFRP levhanın ucunda bir veya iki ankraj olması, iki ankraj ve ilave katman olması ve üç ankraj ve ilave katman olması araştırılmıştır. İlave olarak 60 ve 80 mm genişliğindeki levhalara üç ankraj ve ilave katman yapılmıştır. Üç ankraj yapılan deney elemanlarında levhalar adeta bir gergi çubuğu gibi çalışmış ve betondan tamamen ayrılmıştır. Yapılan deneysel çalışmada 80 mm genişliğinde levhanın ucunda üç adet fan ankraj ve ilave katman olan deney elemanı en başarılı olmuştur. Deney elemanında CFRP levha, kapasitesinin %60'ı oranında yük taşımıştır. Levha genişliği 100 mm olan elemana göre levha genişliği %20 azalmasına rağmen dayanım değişmemiş, levha üzerindeki gerilme artmıştır. Ayrıca levha genişliğinin 60 mm yapılarak daha da azaldığı deney elemanı ise aynı dayanımı sergilemiştir. Ancak göçme şekli istenen formda gerçekleşmemiş, üç ankrajdan sadece biri göçmüştür. Deneylerde 50 mm aralıkla 10 MPa gibi düşük dayanımlı betonda kullanılan 150 mm çapında fan ankrajlarda betondan kaynaklanan göçme gerçekleşmemiştir.
CFRP strips are widely used for repair/strengthening or capacity increase purposes nowadays. Sharp bending at the ends of the CFRP strips is frequently encountered at these applications. In this study, Reinforced Concrete (RC) beam specimens that were produceed with 10 MPa compression strength concrete were strengthened by using bonded CFRP strips with end anchorages to tension region. The parameters that were investigated with this study are the width of the strip, the number of applied fan anchorages and whether additional layer of CFRP patch is used or not at the strip ends. Specimens were strengthened with 100 mm wide CFRP strips with one or two anchorages at the ends. In addition CFRP patch with two and three anchorages at the ends were tested for investigating the effect of the patches. Specimens that were strengthened with three anchorages at the ends with patches were repeated with 60 and 80 mm wide CFRP strips. In the experimental elements with three anchors, the plates worked like a tension rod and were completely separated from the concrete. In the experimental study, the experimental element with three fan anchors and an additional layer at the end of the 80 mm wide plate was the most successful. In the test element, the CFRP sheet carried a load of 60% of its capacity. Although the plate width was reduced by 20% compared to the element with a plate width of 100 mm, the strength did not change, but the stress on the plate increased. In addition, the experimental element, in which the plate width was further reduced by making the plate width 60 mm, exhibited the same strength. However, the collapse did not occur in the desired form and only one of the three anchors collapsed. In the experiments, the 150 mm diameter fan anchors used at 50 mm intervals in concrete with a strength as low as 10 MPa did not collapse due to concrete.
CFRP strips are widely used for repair/strengthening or capacity increase purposes nowadays. Sharp bending at the ends of the CFRP strips is frequently encountered at these applications. In this study, Reinforced Concrete (RC) beam specimens that were produceed with 10 MPa compression strength concrete were strengthened by using bonded CFRP strips with end anchorages to tension region. The parameters that were investigated with this study are the width of the strip, the number of applied fan anchorages and whether additional layer of CFRP patch is used or not at the strip ends. Specimens were strengthened with 100 mm wide CFRP strips with one or two anchorages at the ends. In addition CFRP patch with two and three anchorages at the ends were tested for investigating the effect of the patches. Specimens that were strengthened with three anchorages at the ends with patches were repeated with 60 and 80 mm wide CFRP strips. In the experimental elements with three anchors, the plates worked like a tension rod and were completely separated from the concrete. In the experimental study, the experimental element with three fan anchors and an additional layer at the end of the 80 mm wide plate was the most successful. In the test element, the CFRP sheet carried a load of 60% of its capacity. Although the plate width was reduced by 20% compared to the element with a plate width of 100 mm, the strength did not change, but the stress on the plate increased. In addition, the experimental element, in which the plate width was further reduced by making the plate width 60 mm, exhibited the same strength. However, the collapse did not occur in the desired form and only one of the three anchors collapsed. In the experiments, the 150 mm diameter fan anchors used at 50 mm intervals in concrete with a strength as low as 10 MPa did not collapse due to concrete.
Açıklama
Anahtar Kelimeler
Lifli Polimer, CRFP, Ankraj, Betonarme, Onarım, Güçlendirme, Fibrous Polymer, CRFP, Anchoring, Reinforced Concrete, Repair, Strengthening
