Numerical Study on Seismic Behavior of Prefabricated Shear Wall with Sleeve Grouting Connection After Fire

This research focuses on the seismic performance of post-fire sleeve-grouted connection prefabricated shear walls. The effects of fire duration, axial compression ratio, aspect ratio, and longitudinal bar diameter on the failure mode, horizontal bearing capacity, ductility, and energy dissipation capacity of post-fire sleeve-grouted connection prefabricated shear walls were analyzed using the ‘sequential thermo-mechanical coupling’ method. The research results indicate that the failure mode of post-fire sleeve-grouted connection prefabricated shear walls undergoes significant changes, with damage mainly concentrated in the horizontal joints and the area above the sleeves. As the duration of fire increases, the damaged area gradually extends upwards until the bearing capacity is lost. With the increase in fire duration, the peak and failure loads of post-fire sleeve-grouted connection prefabricated shear walls show a significant downward trend, and the ductility decreases by 7.98%, 12.17%, 15.21%, and 20.15%, respectively. When the axial compression ratio is less than 0.3, both the horizontal bearing capacity and ductility of post-fire sleeve-grouted connection prefabricated shear walls increase with the increase in axial compression ratio. However, when the axial compression ratio exceeds 0.3, the horizontal bearing capacity and ductility of post-fire sleeve-grouted connection prefabricated shear walls decrease with the increase in axial compression ratio, and the failure mode of post-fire sleeve-grouted connection prefabricated shear walls transitions from flexural-shear failure to flexural failure as the axial compression ratio increases. As the aspect ratio increases, the energy dissipation capacity of post-fire sleeve-grouted connection prefabricated shear walls increases, but the horizontal bearing capacity and ductility decrease. Increasing the diameter of longitudinal bars can improve the horizontal bearing capacity of the specimens but reduce the ductility and increase the energy dissipation capacity. The research results provide a theoretical basis for the safety assessment, repair, and reinforcement of post-fire sleeve-grouted connection prefabricated shear walls, and have important reference value for practical engineering applications.