# Shear Performance Study of Sleeved Stud Connectors in Continuous Composite Girder

## TL;DR

This study examines how sleeved stud connectors perform under shear forces, finding they offer better strength and stiffness than traditional welded studs.

## Contribution

The study introduces a novel sleeved stud connector and evaluates its enhanced shear performance through experiments and finite element analysis.

## Key findings

- Sleeved stud connectors showed 4-8% higher ultimate bearing capacity and 25-35% higher shear stiffness than conventional studs.
- The shear behavior of sleeved studs is primarily influenced by sleeve diameter and material rather than stud height.
- Ultra-High Performance Concrete near the stud base significantly improves shear carrying capacity and stiffness.

## Abstract

In order to reveal the mechanism of sleeved stud connectors, 15 push-out specimens were designed, and static loading tests were conducted to evaluate the mechanical performance. The shear performance differences between the novel sleeved studs and conventional welded studs were compared. Referring to the experimental results, an Abaqus nonlinear finite element model was established to study the shear mechanism of sleeved stud connectors. Parametric analysis was conducted to investigate the effects of stud height, sleeve filling material, and sleeve diameter on the mechanical performance of the connectors. The experimental and finite element analysis results indicated that the ultimate shear bearing capacity and shear stiffness of the sleeved stud connectors were higher than those of ordinary welded studs, and the maximum slip was relatively small. Compared to conventional welded studs, the ultimate bearing capacity of sleeved studs increased by 4% to 8%, and the shear stiffness increased by 25% to 35%. Since the shear behavior of sleeved studs mainly occurred at the base of the studs, the influence of stud height on shear performance was relatively small. However, sleeve and stud diameter have a great influence on bearing capacity and stiffness. As the Ultra-High Performance Concrete (UHPC) near the base of the stud effectively enhanced the shear carrying capacity of the sleeved stud connectors, the shear carrying capacity and shear stiffness increased with the increase in the sleeve diameter.