ESTIMATING THE PUNCHING SHEAR CAPACITY OF VOIDED REINFORCED CONCRETE SLAB

Abstract

The study investigates the punching shear capacity of voided reinforced concrete (RC) slabs, which are increasingly utilized in modern construction due to their reduced weight and enhanced structural efficiency. Voided slabs, incorporating spherical or cylindrical voids, aim to mitigate the disadvantages of conventional RC slabs while maintaining structural integrity. Finite element models are developed to simulate their behavior under vertical load, validated by the results of a prior experimental study. The proposed simulation model is subsequently subjected to extensive parametric studies. The deflection of the slab, the crack propagation, and the punching shear capacity are analyzed. The findings reveal that the spacing from the face of the column to the first row of voids significantly influences the punching shear resistance of flat slabs. Additionally, analysis results obtained from the simulation method and those from current codes (ACI and Eurocode) are also discussed in this article. The results provide insights and practical recommendations for the design of voided slabs, suggesting that the first row of voids should be positioned at a distance greater than 1.5D from the column faces.