Experimental characterization of the mechanical behaviour of U-shaped dissipative devices

Energy dissipation devices are used in earthquake engineering in order to reduce the negative effects of ground-motions on structures, thus limiting damage to structural and non-structural components. Different technologies have been proposed to this aim, i.e. viscous fluid dampers, friction-based dampers, hysteretic dampers, etc. Among the different solutions available the present paper focuses on a specific type of hysteretic dampers, U-shaped dissipators. They were first proposed in the 70s and to date have found limited application in the design practice, mainly in buildings with structural walls, exploiting the relative displacement between adjacent walls to dissipate energy. The paper presents the results of an experimental campaign aimed at characterizing the mechanical behaviour of energy dissipators with linear movement, based on U-shaped steel plates. Different configurations were designed and tested, imposing displacement cycles of increasing amplitude. The paper discusses the observed energy dissipation capacity and the stability of the hysteretic cycles.