Experimental and numerical study on behavior of demountable T-shaped bolt shear connectors in sustainable composite beams

• Published in: Construction & building materials 2024-10, Vol.447, p.138070, Article 138070
• Main Authors: Li, Wei, Chen, Wei, Fan, Haitao, Kong, Zhengyi, Xiong, Jingang, Liu, Jicheng
• Format: Article
• Language: English
• Subjects: Demountable composite beam; Finite element analysis; Push-out test; Shear performance; Sustainable
• ISSN: 0950-0618
• DOI: 10.1016/j.conbuildmat.2024.138070

This paper proposed a new type of demountable T-bolt shear connector to improve the disassembly efficiency of composite beams and realize the sustainable of the structure components. The shear behavior of nine groups of push-out specimens was experimentally investigated through monotonic loading push-out tests. The finite element analysis (FEA) models were validated against the test results, specifically in terms of the load-slip responses and failure modes of the T-bolt shear connectors in these push-out specimens. The obtained results show that all the specimens have no obvious deformation and cracks in the steel beam and RC slab. The separation between the slab and the steel beam is no more than 1 mm, indicating that the anti-lifting ability is excellent. Moreover, parametric analysis demonstrates that increasing the bolt pretension of the T-shaped shear connector and the friction coefficient between the bridge gasket and the steel beam significantly enhances the initial stiffness and ultimate strength of the shear connectors. However, the shear behavior is relatively insensitive to variations in the channel thickness and bolt grade. Based on regression analysis, a load-slip mechanical model has been proposed. This model accurately describes the mechanical properties of this type of shear connector, providing a theoretical foundation for the application of demountable composite beams. •A new type of steel beam-concrete slab composite structure was developed to achieve complete disassembly.•The failure mode, load-slip and shear properties of the new non-embedded shear connector were studied.•The model of the push-out test is verified and the parameters are analyzed.•A calculation method suitable for the non-embedded shear connector is proposed.