NUMERICAL STUDY OF CONFINEMENT EFFECT OF FRP COATINGS ON BEHAVIOR OF RC FRAMES BY USING NONLINEAR ANALYSIS
Confinement of both existing and newly constructed reinforced concrete (RC) frames by fibre reinforced polymer (FRP) has been commonly used in recent decades. This is because of its ability to enhance the behavior of RC frames under lateral loading.The purpose of this research is to perform a numerical study on effect of FRP confinement on strength and ductility of RC frames using OpenSEES software.After evaluating the accuracy of numerical model results by comparison with experimental results, the behavior of FRP-resistant frames is discussed.The 8-story studied building is reinforced in various ways by GFRP and CFRP composite sheets.Results of nonlinear analysis show that un-wrapped frame exhibits low resistance and less energy absorption.However, the loading capacity and the performance level have improved significantly in the frames strengthened with FRP materials.Also, increased capacity and reduced drift present more amount of increment in cases which CFRP materials are used.
The authors would like to thank M. Alborzi for valuable comments on the numerical analyses and great help during this research.Discussions with M. Forughi are also appreciated.
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