Evaluating Shear Contribution of FRP To Masonry Walls

Year 2023, Volume: 12 Issue: 2, 105 - 114, 17.11.2023

Zeynep Ünsal Aslan , Metin Karslıoğlu

Abstract

In earthquake-prone regions, there has been a notable focus on employing modern and efficient techniques to enhance the durability of unreinforced masonry walls (URM) in recent years. Among these approaches, the utilization of Fiber Reinforced Polymer (FRP) for strengthening has particularly gained recognition. In this paper, a novel empirical model is presented, employing nonlinear regression analysis, to forecast the shear contribution of FRP strips. URM walls with three configurations of the FRP strips have been considered: one is horizontal FRP strips, the second is vertical FRP strips, and the other is FRP grid strips. The proposed model is developed by using the input parameters determined by considering fourteen different experimental specimens available in the literature, and also considers the influence of reinforcement ratio (ρ0), which was not taken into account in previously suggested models. The FRP strips shear contribution of was competed with the ACI 440.7R-10 model and experimental results. The essential step in any analytical model is evaluating the developed model's accuracy by comparing it with the experimental data and model. This evaluation was performed using the coefficient of determination (R2). The results indicated that the suggested model accurately forecasts the shear contribution of FRP strips and is better aligned with experimental results compared to the ACI 440.7R-10 model.

Keywords

URM, FRP strips, reinforcement ratio, empirical model, horizontal and vertical

Yığma Duvarlarda FRP Kesme Dayanımı Katkısının Değerlendirilmesi

Abstract

Son yıllarda deprem bölgelerinde, donatısız yığma duvarların (URM) dayanıklılığını artırmak için modern ve etkili tekniklerin kullanılmasına dikkate değer bir ilgi olmuştur. Bu yaklaşımlar arasında Fiber Takviyeli Polimerin (FRP) güçlendirme amacıyla kullanılması popülerlik kazanmıştır Bu makale, doğrusal olmayan regresyon analizi kullanarak, FRP şeritlerinin kesme dayanımı katkısını tahmin etmek için yeni bir ampirik model tanıtmaktadır. FRP şeritlerinin üç konfigürasyonuna sahip donatısız yığma duvarları dikkate alınmıştır. Bu konfigürasyonlardan biri yatay FRP şeritlerinin, ikincisi dikey FRP şeritlerinin ve diğeri hem yatay hem dikey FRP şeritlerin birlikte bulunduğu konfigürasyondur. Önerilen model, literatürde yer alan on dört farklı deney numunesi dikkate alınarak belirlenen girdi parametreleri kullanılarak geliştirilmiştir. Ayrıca, önerilen modelde literatürde mevcut modellerde dikkate alınmayan güçlendirme oranının (ρ0) etkisi de dikkate alınmıştır. FRP şeritlerin kesme dayanımı katkısı ACI 440.7R-10 modeli ve deneysel sonuçlarla karşılaştırılmıştır. Herhangi bir analitik modelde temel adım, geliştirilen modelin doğruluğunu deneysel veriler ve modelle karşılaştırarak değerlendirmektir. Bu değerlendirme belirleme katsayısı (R2) kullanılarak yapılmıştır. Sonuçlar, önerilen modelin FRP şeritlerin kesme dayanımı katkısını doğru bir şekilde tahmin ettiğini ve ACI 440.7R-10 modeline kıyasla deneysel sonuçlarla daha iyi uyumlu olduğunu göstermiştir.

Keywords

URM, FRP şeritleri, güçlendirme oranı, ampirik model, yatay ve dikey

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