Assessment of SFRC flat slab punching behaviour – part I: monotonic vertical loading

Abstract

This paper presents a study of the behaviour and load capacity of steel-fibre-reinforced concrete (SFRC) flat slabs under monotonically increased concentrated vertical loads. The SFRC was used only in the local region of the slab–column connection, as the rest of the slab was cast using normal concrete without fibres. The six experimental test specimens had a thickness of 150 mm with different longitudinal reinforcement ratios, using a non-uniform distribution over the slab width. The concretes used were made with different Dramix 4D 65/60 BG steel fibre contents (0, 0·5, 0·75 and 1·0% volume content). The slab tests were complemented by flexural tests on notched beams. This made it possible to determine the tension behaviour of the different concretes used, through a linear post-cracking behaviour and inverse analysis. The inverse analysis made it possible to define the stress–crack opening relationship that characterises the tension behaviour of SFRC and to relate it to the observed behaviour and load capacity of the tested slabs. The tests results show that the tensile behaviour of the SFRC plays an important role in the behavioural and load capacity of the slabs and that it can be considered relevant to physically based models.

Steigerung der Durchstanztragfähigkeit und Duktilität durch die Zugabe moderner Hochleistungsstahlfasern

“…Die Eignung dieser Fasertypen zur Verbesserung der Durchstanztragfähigkeit wurde bereits bei Durchstanzversuchen in gezeigt, jedoch wurden auch hierbei vergleichsweise geringe und wenig praxisrelevante Plattenstärken betrachtet.…”

“…In der Vergangenheit konnte bereits durch zahlreiche Untersuchungen (vgl. ) das Potenzial von Stahlfaserbeton zur Verbesserung der Durchstanztragfähigkeit im Bereich des Decken‐Stützen‐Knotens von Flachdecken gezeigt werden. In Abhängigkeit vom Stahlfasertyp und vom Stahlfasergehalt konnten Steigerungen der Durchstanztragfähigkeit von 30 % bis 60 % im Vergleich zu faserfreien Versuchskörpern erzielt werden.…”

A Novel Feature Selection Approach Based on Tree Models for Evaluating the Punching Shear Capacity of Steel Fiber-Reinforced Concrete Flat Slabs

“…More recently, Gouveia et al [ 18 ] carried out another experimental study aimed at evaluating the punching shear capacity of the SFRC slab-column connections. Moreover, Gouveia et al [ 19 , 20 ] implemented experimental studies to assess the load capacity of the SFRC flat slabs subjected to vertical loads incremented in a monotonic manner as well as reversed horizontal cyclic loading. Another study conducted by Kueres et al [ 21 ] investigated the response of reinforced concrete flat slabs as well as column bases to the punching shear force by employing the fracture kinematics of the slabs.…”

One-way shear and punching strength of reinforced concrete slabs without transverse reinforcement under concentrated loads

“…αcc is factor that accounts for long-term effects on the compressive strength and unfavorable effects from the way load is applied (GOUVEIA et al, 2019a).…”

“…• The proposed approach based on the CSCT (MAYA et al, 2012;MUTTONI, 2008) and inspired by the works of Moreillon (2013), and Gouveia et al (2019a) leads to good predictions of the punching capacity of NSC-UHPFRC slabs with the rational use of UHPFRC around the loaded area and at the compression side. This statement is supported by comparisons between the analytical predictions and the experimental results of Zohrevand et al (2014), as well as by comparisons between the analytical calculations with advanced NLFEA developed in the parametric studies (Section 6.2 and Section 6.3).…”