Reinforced concrete flat slabs with openings at different distances from the column

Diego Da Silva Lourenço,Luiz Carlos De Almeida,Leandro Mouta Trautwein,Elyson Andrew Pozo Liberati,Marília Gonçalves Marques

doi:10.1590/s1983-41952021000100011

Abstract

abstract: The increase in the use of flat slabs and the need of the openings for the passage of installations, such as hydraulic and electrical, which significantly reduces the punching shear resistance capacity of the slab, makes the understanding of the influence of openings in this type of structure extremely necessary. The influence in the structural behaviour of flat slabs with openings at different distances from the column was investigated through five square slabs (1,800 mm x 1,800 mm x 130 mm) supported on square columns (150 mm x 150 mm) tested until failure. The results obtained experimentally were compared with results available in the literature, as well as with responses predicted from the normative instructions. The results confirm high stresses concentration in the region between the column and the opening and that opening situated at 3d from the column have no influence on the failure load for the tested slabs.

Highlights

Reinforced concrete flat slabs without shear reinforcement are commonly used in many structural systems, such as flat slabs of buildings and parking garages
This study presents the results of the experimental program involving reinforced concrete flat slabs without shear reinforcement subjected to concentric punching shear
The present study aims to reproduce the structural behavior of reinforced concrete flat slabs in the region around internal columns

Summary

Introduction

Reinforced concrete flat slabs without shear reinforcement are commonly used in many structural systems, such as flat slabs of buildings and parking garages. The flat slab system presents a complex behavior, especially in the slab-column connection. Failures in punching of flat slabs without shear reinforcement develop in a brittle manner with limited deflections and are followed by an almost complete loss of the load carrying capacity (Figure 1).

Methods

Results

Conclusion