Non-linear finite element and theoretical analyses of a timber–concrete composite floor slab with inclined connectors

Abstract

Timber–concrete composite floor is an emerging option for the construction industry, and some recent works have studied the effect of inclined connectors in such a system. However, parameters influencing their mechanical behaviours have not been extensively studied. Hence, this study examines the influence of the different components using a newly developed non-linear finite element (FE) modelling. The developed FE model was validated using experimental data available in the literature. The non-linear behaviour was considered as an elastoplastic hardening material model incorporating Hill’s yield criterion. Subsequently, the FE model was used to conduct a parametric study to examine the influence of several parameters on the mechanical response of the composite floor. The study revealed that the concrete strength played an essential role in the overall strength of the beam and ductility. Increasing the concrete strength from 21 MPa to 35 MPa led to an increase in load carrying capacity by 31.9%. Varying the timber properties variables (tensile strength and elastic modulus) and shear connectors arrangement resulted in changes in the overall strength but also the stiffness of the composite. The load carrying capacity ranged from −2.12% to 6.55% and the deformation decreased by up to 28.98% for the GL36h sample. In addition, the comparison of the plastic moment resistance of each condition was probed, indicating an impactful influence on the plastic stress distribution between all major parts of the composite system. In general, increasing the timber grade resulted in a drop in the plastic moment whereas increasing the concrete strength increased the plastic moment resistance.

Keywords

Non-linear finite element model / Timber–concrete composite / Inclined connectors / Parametric study / Theoretical analysis

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Funding

XJTLU(RDF 20-02-12)

RIGHTS & PERMISSIONS

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