Tekstil takviyeli harçlarla güçlendirilen beton kirişlerin eğilme performansı: Uygulama deseni ve onarım harcı tipinin etkisi

Öz

Bu çalışma, normal dayanımlı beton kirişlerin eğilme performansını iyileştirmek amacıyla yüksek fırın cürufu bazlı geopolimer harcı ve çimento esaslı ticari bir tamir harcı kullanılarak üretilen tekstil donatılı harç (TRM) sistemlerinin etkinliğini incelemiştir. TRM uygulamaları farklı desen ve kaplama oranlarıyla değerlendirilmiş; ayrıca karşılaştırma amacıyla beton karışımlarına %0.3 ve %0.6 oranlarında çelik lif katkısı ilave edilmiştir. Eğilme dayanımı, yük-deplasman davranışı, rijitlik, süneklik ve enerji yutma kapasitesi gibi parametreler üzerinden yapılan değerlendirmeler sonucunda; tam yüzey TRM uygulamalarının taşıma kapasitesini %24'e varan oranda artırdığı, geopolimer esaslı TRM sistemlerinin ise hem sınırlı hem de tam kaplama koşullarında çimento esaslı sistemlerle kıyaslanabilir hatta üstün performans gösterebildiği ortaya konmuştur. %0.6 lif katkısı ise süneklik ve enerji yutma açısından sınırlı iyileştirme sağlarken, rijitlikte belirgin bir azalmaya neden olmuştur. Elde edilen sonuçlar, özellikle doğru kaplama deseni ve bağlayıcı seçimiyle uygulanan TRM sistemlerinin betonarme elemanların eğilme davranışını iyileştirmede etkili ve sürdürülebilir bir yöntem olduğunu ortaya koymuştur.

Anahtar Kelimeler

• Geopolimer
• Tekstil takviyeli harç
• Onarım
• Çelik lif
• Eğilme dayanımı

Flexural Performance of concrete beams strengthened with textile reinforced mortars: Influence of application pattern and repair mortar type

Abstract

This study examines the effectiveness of textile-reinforced mortar (TRM) systems incorporating a ground granulated blast furnace slag-based geopolymer mortar and a commercially available cement-based repair mortar in enhancing the flexural performance of normal-strength concrete beams. TRM applications were implemented with varying coverage patterns and surface areas, while steel fibers were added to the concrete mixtures at dosages of 0.3% and 0.6% by volume for comparative purposes. Experimental evaluations—including flexural strength, load–displacement behavior, initial stiffness, ductility, and energy dissipation capacity—revealed that full-coverage TRM applications enhanced load-bearing capacity by up to 24%. Geopolymer-based TRM systems exhibited comparable or even superior performance to their cement-based counterparts under both full and partial coverage conditions. While the incorporation of 0.6% steel fiber contributed to modest improvements in ductility and energy absorption, it also resulted in a significant reduction in initial stiffness. These findings highlight that TRM systems—particularly when applied with optimized coverage geometry and appropriate binder type—constitute an effective and sustainable strategy for improving the flexural response of reinforced concrete elements.

Keywords

• Geopolymer
• Textile reinforced mortar
• Repair
• Steel fiber
• Flexural strength

Kaynakça

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