Horizontal push out tests on a steel-yielding demountable shear connector

[EN] The most common type of a steel concrete composite beam is the one using conventional welded headed studs to connect the top flange of a steel beam to the concrete slab. However, the monolithic structure between the headed studs and the concrete slab prevents the deconstruction of the beam. More sustainable solutions in construction can be achieved by developing demountable connections which allow for fully deconstruction and reuse of all structural systems. This paper presents a novel demountable shear connector for use in steel concrete composite beams in conjunction with precast hollow core slab units. The demountable connection proposed has the advantages of minimal use of in situ concrete required only in specific regions, increased ductility due to the unique shape of the shear connector and since it is not embedded in in situ concrete, it facilitates the deconstruction procedure. Ten horizontal push out tests aiming at investigating the structural performance of the demountable shear connector were carried out. The strength of the connection is predicted using simple mechanics based on plastic beam analysis. The experimental results showed that the proposed demountable shear connector can achieve increased strength depending on the geometric characteristics of the connector, a ductile slip-load curve and a very high slip capacity.Feidaki, E.; Vasdravellis, G. (2018). Horizontal push out tests on a steel-yielding demountable shear connector. En Proceedings of the 12th International Conference on Advances in Steel-Concrete Composite Structures. ASCCS 2018. Editorial Universitat Politècnica de València. 221-228. https://doi.org/10.4995/ASCCS2018.2018.7073OCS22122

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