A new analytical formulation for the stiffness and resistance of the additional plate in bending in beam-to-beam steel joints

[Display omitted] •Study of beam-to-beam bolted steel joints attached by an additional plate.•Execution of experimental tests to validate a finite element model.•Development of a parametric study with finite element models.•Development of an analytical formulation based in an equivalent frame.•Presentation of analytical expressions for stiffness and resistance. This paper focuses on the stiffness and resistance of the additional plate in bending. This is a component which appears in beam-to-beam bolted steel joints, when a secondary beam with a flush end plate is attached orthogonally to the primary beam by an additional plate welded between its flanges. In this work, six experimental tests have been carried out to calibrate a finite element model which has been used to develop a wide parametric study. Thus, a new formulation for stiffness and resistance based on an equivalent frame is proposed.