Abstract (EN):
The panel zone component of a steel connection plays a fundamental role on the global behaviour of a moment-resisting frame. Whilst the treatment of this component for gravity loads is perfectly established in design codes, the situation is rather different when seismic design is considered. The classification of this connection component is generally based on the ratio between the panel zone strength and the flexural capacity of the connecting beams. The difference between these three approaches is found on the level of energy dissipation that develops on the panel zone [2,10]. Strong panel zones are designed to remain elastic during a seismic event. In that case there is no energy dissipation developing on this component. Conversely, if weak panel zones are considered, most of the energy dissipation during an earthquake will occur on these components. In the past the panel zone was typically designed to respond elastically to the design earthquake. However, experimental testing conducted since the early 1970’s has shown that panel zones are capable of develop large inelastic deformations and exhibit stable hysteretic behaviour [1,4,7]. These observations were reflected in important changes in design codes which currently allow for this component to respond inelastically during an earthquake [5,13,16]. However, some authors have reported that the application of a recently proposed design approach [13] that seeks the achievement of balanced panel zones does not necessarily result in an effective participation of these components to the inelastic response [6,15]. Nevertheless, the benefits of using balanced panel zones have been recently demonstrated by the authors of this paper [15]. Even reduced participation of panel zones in the inelastic response contribute to reduce the plastic demands imposed on other structural components. The objective of this paper is to identify the impact of different panel zone design approaches on the level of participation of these connection components to the response. Special attention is paid in quantifying the relative contribution of panel zones to the total joint plastic rotation in moment-resisting frames. To this end, a parametric study involving several steel moment frames is carried out in which the panel zones are designed according to different approaches. The behaviour assessment is then conducted through non-linear static analyses.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica