Evaluation of Seismic Performance of Concrete Structures Retrofitted with FRP Composites

Document Type : Articles

Authors

1 Department of Civil Engineering, Sanandaj Branch, Islamic Azad University, Sanandaj, Iran

2 Department of Civil Engineering, Marivan Branch, Islamic Azad University, Marivan, Iran

Abstract

The present paper aims at investigating the effects of strengthening structural components of reinforced concrete (RC) frames using FRP composite on their seismic performance. For this purpose, in a case study, the seismic performance of a typical building with moment frames in both plan directions as the lateral force resisting system and retrofitted with FRP wraps to deal with the weaknesses arose from increase in the number of stories compared to the original structure for occupancy reasons has been evaluated. Strengthening of the columns has been performed by considering the axial force and the biaxial bending moments at target displacement, while that of the beams has been performed based on the bending moments at the target displacement. The seismic performance of the strengthened structure has been investigated by nonlinear analysis methods based on concentrated plastic hinges model following ASCE 41-17 standard procedures. The results show that the use of FRP composites in strengthening RC components significantly improves the seismic performance by reducing the number of plastic hinges as well as the plastic rotation demands at the target displacement of the retrofitted structure.

Keywords


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