Dissipating Effect of Glazed Curtain Wall Stick System Installed on High-Rise Mega-Braced Frame-Core Buildings Under Nonlinear Seismic Excitation

Abstract

Abstract. The results derived from the investigation on the dynamic behavior of glazed curtain wall non-structural stick systems installed in modern high-rise mega-frame prototypes is herein summarized. The supporting steel structures, designed in accordance with European rules, consisted of planar frames extracted from reference three-dimensional steel Moment Resisting Frame (MRF), respectively having thirty-and sixty-storey height. To limit interstorey drift and second order effects, outriggers trusses were placed every fifteen stories, whilst a CBF system was chosen as internal core. The characterization of non-structural façade elements was performed through experimental full-scale crescendo-tests on aluminium/glass curtain wall units. Deriving experimental force-displacement curves, it was possible to calibrate threedimensional inelastic FE models, capable to simulate the interaction between glass panels and aluminium frame. Subsequently, equivalent nonlinear links were calibrated to reproduce the dynamic behaviour of tested glazed unit, and implemented in the thirty-and sixty-storey structural planar frames FE models. Nonlinear time history analyses (NLTHAs) were performed to quantify local and global performance, investigating the enhanced combination of stiffness and strength generated through the implementation of glazed curtain wall on the numerical FE models. Results will be shown in terms of inter-storey drift profiles and displacement peaks, axial force curves and percentage peak variation, showing the sensitivity to the structure height. Trends were discussed to show that, if accurately designed, omitting non-structural elements from the seismic assessment of high-rise prototypes conduct to a sensible underestimation of dynamic dissipation capacity of the building.

A Pseudoelastic Floor Isolation System for Hospital Seismic Retrofitting

“…Therefore, we develop 3D finite element (FE) models by means of the software ABAQUS [15], employing 8-node brick-based models in an isoparametric framework, in accordance with [20]. Geometrical and material non-linearities are considered.…”