FINITE ELEMENT ANALYSIS OF THE MECHANICAL BEHAVIOR OF REINFORCED CONCRETE (RC) BEAMS STRENGTHENED BY FIBER REINFORCED POLYMERS (FRP)

Year 2020, Volume: 38 Issue: 2, 687 - 702, 01.06.2021

Ceren Gökcen Emin Hökelekli Emre Ercan Mehmet Erkek

Abstract

The reason for the extensive use of fiber reinforced polymers (FRP) as a reinforcement material in construction elements is due to its advantageous mechanical properties. The mechanisms underlying the failure of FRP reinforced concrete beams is still a phenomenon in question for researchers. The best means of determining the mechanical behavior of a construction element is usually by laboratory testing. But this process takes a lot of time and is costly. Only a limited number of specimens with certain sizes can be tested and decent experimental equipment and samples may not be easily available. The aim of this study is to develop a finite element model for simulating the behavior of FRP strengthened reinforced concrete (RC) beams reducing the need for experimentation. For this reason, in this study, test results carried out by the Swiss Federal Material Testing and Research Laboratory on FRP strengthened RC beams [7] were compared with results obtained by computer simulation using finite element method. The regions of damage occurrence obtained from the analysis were evaluated and the comparison of the failure load of the simulation with that of the test was made with the load-displacement graphs. The failure loads obtained by the simulations were in good agreement with the test data. Therefore finite element simulations can be used as a tool for predicting the mechanical behavior of FRP strengthened RC beams.

Keywords

FRP, de-bonding behavior, fracture, finite element method

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