Effect of rebar diameter on the shear behavior of Y-shaped shear connectors: A finite element study

Subject Areas : Structural Engineering in Energy-Efficient Buildings

Maede Davami ^{1 *} , علیرضا میرزا گل تبار روشن ² , Hamidreza Tavakoli ³

1 - 1 Department of Civil Engineering, Babol Noshirvani University of Technology (NIT), Babol, Mazandaran, Iran)
2 - دانشگاه صنعتی نوشیروان بابل، دانشکده مهندسی عمران
3 - Babol Noshirvani University of Technology

Received: 2025-10-25 Accepted : 2025-11-13 Published : 2025-11-15

Keywords: Shear connector, Rebar diameter, Finite element analysis, Load–slip curve, Ductility, Y-shaped connector,

Abstract :

This study investigates the influence of rebar diameter on the shear performance of Y-shaped shear connectors in steel–concrete composite beams under ambient temperature. A detailed three-dimensional finite element (FE) model was developed in ABAQUS 6.14, incorporating nonlinear material behavior, realistic contact interactions, and appropriate boundary conditions to replicate push-out tests. The model was validated against experimental data from Kim et al. , showing excellent agreement in load–slip response and failure mode.

Five connector models with rebar diameters of 8, 10, 12, 14, and 16 mm were analyzed while maintaining identical concrete and geometric parameters. The simulation results revealed that increasing rebar diameter significantly enhances both shear strength and stiffness of the connector, but slightly reduces ductility. Stress contour analysis showed that larger diameters lead to a more uniform stress distribution at the connector–concrete interface, reducing localized damage near the connector root.

The optimum rebar diameter range was identified as 12–14 mm, providing the best balance between strength, stiffness, and deformation capacity. The developed FE model and the findings of this study can serve as a reliable numerical foundation for the design and optimization of novel Y-shaped shear connectors in composite beam applications.

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