Experimental study on the seismic behaviors of RC shear walls under the freeze-thaw environment action

Abstract:

The freeze-thaw cycling tests for 6 pieces of RC shear wall specimens with span ratio 2.14 were conducted by artificial climate laboratory, and quasi-static experiments were implemented. The hysteresis loops with different concrete strength grade and freeze-thaw cycles were obtained, and the skeleton curves were achieved. The effects on seismic performance indicators including the ultimate capacity, rigidity, ductility and energy dissipation capacity were analyzed. Results show that with freeze-thaw cycles increasing the bearing capacity of the RC shear wall, the displacement ductility coefficient and the plastic corner decrease significantly, while the strength attenuation and stiffness degradation rate increase, and the energy dissipation capacity decreases. Along with the enhancement of concrete strength grade by same freeze-thaw cycles, the bearing capacity and accumulated energy are improved, then the strength attenuation and stiffness degradation rate are reduced, but the ductility decreases after increasing at first. It indicates that with the concrete strength increasing the RC shear wall has better seismic performance after freezing and thawing.