Yüksek Sıcaklık Etkisindeki CFRP Donatıların Dayanım Kayıplarının Matematiksel Yöntemlerle Tespiti

Year 2023, , 926 - 942, 15.09.2023

Şeymanur Arslan , Ferhat Aydın

https://doi.org/10.31466/kfbd.1273294

Abstract

Liflerle güçlendirilmiş polimer (FRP) donatılar günümüzde çelik donatıya alternatif olarak kullanılmaktadır. Ancak FRP donatılar yüksek sıcaklıklara karşı hassas bir malzemedir. Bu nedenle bu malzemelerin yüksek sıcaklıklardaki çekme dayanımındaki değişimiyle alakalı tahmin modellerinin oluşturulması önem arz etmektedir. Bu çalışmada literatürdeki CFRP donatıların yüksek sıcaklıklarda meydana gelen çekme dayanımındaki kayıpları araştırılmış ve literatürde üç araştırmacı tarafından sunulan matematiksel modellerle deneysel sonuçlar regresyon ve korelasyon analizleri yapılarak kıyaslanmıştır. Alternatif yeni bir model sunmak amacıyla literatürdeki CFRP (karbon fiber takviyeli polimer) donatıların yüksek sıcaklıklardaki çekme dayanımındaki değişimlerinin deneysel verileri incelenerek analiz edilmiştir. Çalışma sonucunda 60°C sıcaklık seviyesinin CFRP donatıların mekanik ve fiziksel özelliklerinde zarar görmediği bu nedenle bu sıcaklık seviyesinin öncesinde dayanım kaybı olmadığı ve bu sıcaklık sonrasında parabolik bir değişiminin olduğu kabulü yapılarak alternatif matematiksel model oluşturulmuştur. Sonuç olarak önerilen yeni modelin deneysel çalışmalarla uyumlu olduğu modelin yapısal uygulamalarda etkili bir tahmin aracı olabileceği düşünülmektedir.

Keywords

Yüksek sıcaklık, CFRP donatı, matematiksel model, çekme dayanımı

Determination of Strength Loss of CFRP Bars Under High Temperature by Mathematical Methods

Abstract

Fiber reinforced polymer (FRP) bars are currently used as an alternative to steel reinforcement. However, FRP bars are sensitive to high temperatures. For this reason, it is important to establish prediction models related to the change in tensile strength of these materials at high temperatures. In this study, the tensile strength losses of CFRP bars at elevated temperatures were investigated and the mathematical models presented by three researchers in the literature were compared with the experimental results through regression and correlation analyses. In order to present a new alternative model, the experimental data of CFRP (carbon fiber reinforced polymer) bars at high temperatures were analyzed As a result of the study, an alternative mathematical model was created by assuming that the 60°C temperature level does not damage the mechanical and physical properties of CFRP reinforcements, therefore there is no strength loss before this temperature level and there is a parabolic change after this temperature. As a result, it is thought that the proposed new model is compatible with experimental studies and can be an effective prediction tool in structural applications.

Keywords

Elevated temperature, CFRP bar, Mathematical model, Tensile strength

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