[en] To successfully facilitate the construction sector's transition toward sustainability, there is an urgent need for alternatives to the existing practices which are not sustainable. Steel-timber composite (STC) beams, which combine a down-standing steel beam and a timber slab for flooring systems, show large potential as sustainable alternative to conventional steel-concrete composite systems. In STC systems the shear connection is a key element that keeps the elements together and ensures effective composite action. This study presents a comprehensive experimental assessment of novel shear connections for demountable STC beams and flooring systems. The research focused on three newly developed bolted shear connector types: SCT-1, SCT-2, and SCT-3, each incorporating a different shear connection device designed to protect the timber and enable the attainment of the required preload for high-strength bolts. These novel shear connections represent a robust and sustainable alternative to conventional connections, offering superior protection to structural elements. The connections were tested in a double-symmetric push-out test setup, implementing laminated veneer lumber (LVL) plates connected to HEB steel profiles. Their performance was assessed in terms of their load-slip responses, stiffness, and failure mode. The load-slip responses were found to be nonlinear, and the connectors exhibited a significant deformation capacity (greater than 40 mm slip). The results of this study indicate load-bearing capacities per shear connector at a 6 mm slip of 95.7 kN, 104.4 kN, and 120.2 kN for SCT-1, SCT-2, and SCT-3, respectively. Additionally, the maximum loads per shear connector were recorded as 161.4 kN for SCT-1, 173.1 kN for SCT-2, and 163.8 kN for SCT-3. Furthermore, the shear connections introduced in this study offer ease of installation and facilitate the assembly and disassembly of components.
Disciplines :
Ingénierie civile
Auteur, co-auteur :
ROMERO, Alfredo ; University of Luxembourg > Faculty of Science, Technology and Medicine (FSTM) > Department of Engineering (DoE)
ODENBREIT, Christoph ; University of Luxembourg > Faculty of Science, Technology and Medicine (FSTM) > Department of Engineering (DoE)
Co-auteurs externes :
no
Langue du document :
Anglais
Titre :
Experimental investigation on novel shear connections for demountable steel-timber composite (STC) beams and flooring systems. (LAJ24.B)
The authors gratefully acknowledge the Luxembourg’s National Research Fund (FNR), Prefalux, ArcelorMittal and MetsäWood for their support in the research project Prefa-SeTi: Steel-Timber Composite Beams (PhD Industrial Fellowship Grant No. 15695062). The authors wish to thank also the laboratory team (Gilbert Klein, Marc Seil and Ed Weyer) and the former student Melis Pelivani for their support in this testing campaign.This research was funded by Fonds National de la Recherche Luxembourg (FNR) and PREFALUX , and supported by ArcelorMittal Luxembourg , within the framework of the research project '' Prefa-SeTi: Steel-Timber Composite Beams '', which is a PhD Industrial Fellowship Grant No.: 15695062 .
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