Punching shear failure is a common issue in the connection between flat slabs and reinforced concrete columns. Once failure occurs, a supplementary load-carrying mechanism is necessary to prevent the progressive collapse of the connections. This study presents an experimental program and a theoretical model to investigate the punching shear and post-punching behavior of seven flat slabs with different concrete types and reinforcement configurations. The effects of wire mesh, fiber-reinforced concrete, and integrity bars on punching shear failure and post-punching behavior in internal slab-column connections were analyzed. The results indicate that incorporating integrity bars and fibers into the concrete enhances both punching and post-punching shear strength. The experimental findings demonstrated a significant enhancement in both punching strength and maximum post-punching load, exhibiting respective increments of 32% and 28% relative to the specimen without fiber reinforcement. Furthermore, fiber integration within the wire mesh matrix substantially improved the structural ductility of the slab. Notably, the synergistic combination of fiber reinforcement and wire mesh demonstrated a 103% greater energy dissipation capability compared to the baseline configuration lacking both components. This substantial enhancement underscores the influence of optimized material composition and reinforcement strategies in mitigating deformation and improving structural resilience.

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