Six new details for composite steel–concrete connections are proposed for a continuous concrete column and a steel beam segment. A steel sleeve is used to connect the steel beam to the concrete column. Connection components are either steel studs or U-channels used in two different types of joints to connect the sleeve to the concrete column. Attachment of beam to the sleeve is in three different ways including direct connection, using steel plates at beam flange levels, and utilizing apron plates all around the column at beam flanges. The behavior of the connections is evaluated, and stiffness, strength, and ductility of the suggested connections are compared with the conventional steel and concrete joints. Effects of axial load, beam size, steel sleeve thickness, and height of steel sleeve are investigated. Based on the results of this study, appropriate ranges for the thickness and height of the steel sleeves are determined. In addition, some optimized design parameters are proposed in order to improve the behavior of the connections. The proposed connections are categorized based on their strength and ductility for use in ordinary, moderate, and special frames.
