Title:
Finite Element Analysis and Design of Shear Behaviour of RC Slabs Supported on Walls
Author(s):
Graeme J. Milligan, Maria Anna Polak and Cory Zurell
Publication:
Symposium Paper
Volume:
365
Issue:
Appears on pages(s):
1-16
Keywords:
finite element analysis, punching shear, Reinforced Concrete Slabs, Slab-Wall Connections, Unbalanced Moment, Design Methods
DOI:
10.14359/51746680
Date:
3/1/2025
Abstract:
Due to the low lateral stiffness of slabs supported on columns alone reinforced concrete flat plates are typically combined with other structural elements, such as shearwalls. In these structures, the slab-column connections are designed to carry gravity loads only, and the shearwalls, which also carry gravity loads, are required to resist the lateral forces. Therefore, the slab-wall connections (SWCs) are essential for the adequate performance of both the gravity and lateral force resisting systems. However, the majority of punching shear research and design provisions have been focused on slab-column connections, even though punching failures around slab-wall connections have been observed experimentally. Empirical testing of slab-wall connections is difficult due to the required specimen size. This paper investigates the punching shear behaviour of interior slab-wall connections subjected to concentric vertical loading, and combined concentric vertical loading and uniaxial unbalanced moment using a plasticity-based nonlinear finite element model (FEM) in Abaqus. The FEM, developed to study the impact of column aspect ratio on punching shear, was calibrated considering seven isolated slab-column specimens. The analysis of isolated slab-wall connections demonstrates that punching failures can occur before one-way shear failures, although the connection capacity is much higher than the expected loads in most structures. Punching shear design methods for interior slab-wall connections subjected to gravity load only, developed from finite element analysis results, are developed and presented in the paper.
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