Post-fire cyclic behavior of reinforced concrete shear walls

Abstract

The effects of fire exposure, reinforcement ratio and the presence of axial load under fire on the seismic behavior of reinforced concrete (RC) shear walls were investigated. Five RC shear walls were tested under low cyclic loading. Prior to the cyclic test, three specimens were exposed to fire and two of them were also subjected to a constant axial load. Test results indicate that the ultimate load of the specimen with lower reinforcement ratio is reduced by 15.8% after exposure to elevated temperatures. While the reductions in the energy dissipation and initial stiffness are 59.2% and 51.8%, respectively, which are much higher than those in the ultimate load. However, this deterioration can be slowed down by properly increasing reinforcement due to the strength and stiffness recovery of steel bars after cooling. In addition, the combined action of elevated temperatures and axial load results in more energy dissipation than the action of fire exposure alone.

Keywords

shear wall / reinforced concrete / post-fire / seismic behavior / low cyclic loading

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