Structural Behavior of Steel-Concrete Composite Girders Composed of Demountable Shear Connectors

In recent years, many studies on demountable shear connectors have been conducted to facilitate the dismantlement and replacement of precast slabs for steel-concrete composite bridges. Welded headed studs are still mainly used for the horizontal shear synthesis of steel girders and precast concrete slabs, and are adopted in Korean design standards. Because the service life of concrete slabs is much shorter than that of steel girders, however, easy replacement of damaged or old slabs will improve the economic feasibility of the entire bridge during its service life. Therefore, in this study, a new concept of bolted shear connectors is proposed for easy deconstruction and reconstruction of precast concrete slabs. The structural behavior of the proposed connector was verified through horizontal shear and bending tests on composite girder specimens. The connector demonstrated sufficient synthesis performance to replace the conventional welding stud. It also satisfies the current ductility design criterion and flexural performance for slip displacement; hence, we conclude that the novel connector can be used under the existing design standards.