Static Capacity Curves of Reinforced Concrete Structures Exposed to High Temperature Effects

Abstract

In this study, it is aimed to investigate the seismic performance of a reinforced concrete (RC) structural system exposed to high temperatures. For this purpose, a RC structure with 4 floors and 4 spacings was designed. First of all, column and beam elements were modeled by using ANSYS software and then, thermal analysis was performed assuming that they were exposed to the standard fire curve to obtain the temperature distributions in the cross-sections of the reinforced concrete elements. Secondly, the sectional analyses were performed for the reinforced concrete element sections and moment-curvature relations were obtained. Finally, the three dimensional (3D) structural system was modeled and static pushover analysis was carried out in accordance with the Turkish Building Earthquake Code (TBEC 2018). The results showed that as the exposure time to high temperature increase the inelastic displacement capacity and the base shear force values decrease. The results were also affected by the location of the fire event. Besides, plastic hinges occurred more quickly than the situation before fire event, resulting in a decrease in the load carrying capacity and stiffness of the system.

Keywords

• RC elements
• High temperatures
• Pushover analysis
• Sectional response
• Finite elements

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