Debonding and Fracture Behavior of Concrete Specimens Retrofitted by FRP Composite

Document Type : Original Article


1 M.Sc. Student, Faculty of Civil Engineering, Istanbul Technical University, Istanbul, Turkey

2 Assistant Professor, Faculty of Civil Engineering, Azarbaijan Shahid Madani University, Tabriz, Iran


The effects of FRP retrofitted concrete specimens with couple of notches on the fracture behavior have been investigated during an experimental and analytical test program in this study. This paper represents the fracture characteristics and parameters for three point bending tests on two distinguish retrofitted and plain condition for both intact and notched (couple notches) specimens. The experimental test results find out in the laboratory tests indicated that for intact concrete specimens, there would be approximately 285% increase in ultimate flexural strength tests. The experimental results also represents that for the tested couple notched concrete specimens, there might be approximately 318% increase in ultimate flexural strength. Based on the analytical study, it is found that the near failure behavior of the notched specimens have been significantly improved using FRP retrofit of such specimens. The system`s global energy balance and failure load prediction of FRP debonding are the couple of consideration by a developed fracture mechanics based model which made by energy dissipation major mechanisms characterizing while debonding. Model verification is provided using previous researches experimental data from literature. In addition, fracture mechanics parameters were found out for three point bending test in this paper for better understanding on fracture behavior and fracture properties of intended specimens.


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