FEM analysis of punching shear in reinforced concrete slabs: role of concrete-steel interface
The connection between flat reinforced concrete slabs and columns represents a critical design challenge in structural engineering, particularly in buildings, due to the substantial concentration of shear stresses that can lead to punching failure. This localized, brittle failure mechanism occurs ab...
| Autores: | , |
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| Tipo de recurso: | libro |
| Fecha de publicación: | 2026 |
| País: | España |
| Institución: | Universidad de Jaén |
| Repositorio: | RUJA. Repositorio Institucional de la Producción Científica de la Universidad de Jaén |
| OAI Identifier: | oai:ruja.ujaen.es:10953/7596 |
| Acceso en línea: | https://hdl.handle.net/10953/7596 |
| Access Level: | acceso abierto |
| Palabra clave: | Punching-shear Finite element method Cohesive model Concrete-steel interface Construction Materials |
| Sumario: | The connection between flat reinforced concrete slabs and columns represents a critical design challenge in structural engineering, particularly in buildings, due to the substantial concentration of shear stresses that can lead to punching failure. This localized, brittle failure mechanism occurs abruptly, without prior warning, and carries a considerable risk of structural collapse. Despite extensive research aimed at understanding the mechanics governing punching shear failure and developing dependable design methodologies, such as the Critical Shear Crack Theory (CSCT), a unified understanding of the underlying phenomena remains elusive. This investigation makes use of the Finite Element Method (FEM) in conjunction with material models based on fracture mechanics to simulate punching shear failure in reinforced concrete slabs. While this methodology has been previously explored, challenges persist, particularly in accurately representing the overall response of the problem and the failure mechanisms involved. The objective of this work is to evaluate various modelling approaches to establish a numerical model capable of accurately reproducing this phenomenon, thereby offering insights into the intricate fracture mechanisms that drive the failure process. The numerical simulations draw upon experimental data from Kinnunen and Nylander’s seminal work, specifically referencing specimens IA15a, IB15a and IC15a. These slabs are circular, with a diameter of 1840 mm, are supported by a 150 mm diameter column, with both the column height and slab thickness being 150 mm, and incorporate different reinforcement strategies. While IA15a slab presents an orthogonal reinforcement, IB15a is reinforced with ring reinforcement and IC15a with a combination of ring and radial reinforcement. The experimental setup involves applying load from below the specimen using a hydraulic jack, while the slab’s perimeter is constrained vertically by twelve spreader beams. The FEM models employ an isotropic damage formulation to describe concrete behaviour, where damage reduces the material’s stiffness and is determined using an equivalent strain value based on the Rankine criterion. Steel is represented by a perfectly plastic material, adhering to the von Mises plasticity condition. A key focus of this study is the examination of the concrete-steel interface behaviour. Two distinct model versions are prepared for each of the three slabs: one of them assume perfect bonding between steel and concrete and do not allow debonding, while the other one permits perfect slippage between concrete and steel. The numerical findings underscore the critical importance of accurately modelling the concrete-steel interface. Notable differences in the load-displacement diagrams between those models where slippage is not allowed and those where it is allowed, emphasize the significant influence of bond-slip behaviour in accurately capturing the punching shear response of reinforced concrete slabs. This research contributes to a deeper understanding of punching shear failure and supports the development of more reliable numerical tools for structural design. |
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