Circular openings with transverse rebar as steel-concrete shear connection (part 2/2): Experimental investigation, model validation and parametric analysis

Abstract

Aiming to better utilize the strength and slip capacity of Circular Openings with Transverse Rebar shear connectors when subjected to concrete confinement, situation in which failure mode is governed by the transverse rebar, an experimental program was specifically designed to isolate the mechanisms that develop locally in each confined opening and the influence exerted by different geometric and material parameters. Based on the experimental observations and analysis drawn from these tests, an analytical model capable of predicting whole load-slip curves was proposed and, with it, a parametric analysis was performed. The analytical model formulation is presented in the part 1/2 of this publication. This paper is the part 2/2 of the publication and presents 1) experimental results, observations, and analysis, 2) experimental validation of the proposed analytical model using experimental data from this work and from literature, and 3) a parametric analysis, in which it was investigated the influence that each of the connection’s main geometric and material parameters exert on its strength and slip capacity. This parametric analysis, together with the experimental observations and the analytical model formulation, provide a deep understanding of the connection’s behavior under confinement, which can be used for designing composite elements with optimized composite interaction and ductility.