Progressive collapse mitigation of 2D steel moment frames

Abstract

to describe the concept of the progressiveness of damage and the quantification of the property of structural systems to resist progressive collapse. Another pioneering paper presenting many aspects of progressive or disproportionate collapse analysis is [4], which highlights the distinction between direct and indirect methods of analysis and introduces tools associated with the measurement of risk arising from abnormal hazards that can trigger progressive collapse.Numerous researchers have studied the problem of steel buildings under extreme conditions through a multitude of different approaches ([5] to [15]). The work in [16] and, in particular [17] emphasized at a conceptual level the critical importance of investigating the global stability of the structure when performing progressive collapse analyses as well as the need to examine the global response of a damaged structural system.The present paper utilizes the findings included in [17] and [18], comprehensively examines the instability of 2D steel frames when exposed to progressive collapse and investigates the effect of different strengthening schemes on the progressive collapse capacity of a structure.2 Progressive collapse analysis of moment-resisting steel frames 2.1 Description of frames, FEM models and applied loadsThe moment-resisting steel frames are modelled in 2D and shown in Fig. 1: four 4-bay frames with 15, 12, 9 and 6 floors. The storey height is 3 m and the bay width is 5 m, resulting in total heights of 45, 36, 27 and 18 m respec- Progressive collapse mitigation of 2D steel moment framesAssessing the effect of different strengthening schemes Simos Gerasimidis Charalampos BaniotopoulosThe problem of the progressive collapse of structures is today at the forefront of structural engineering because of multiple natural and man-made hazards, the aging of the infrastructure and the catastrophic consequences associated with that. This paper investigates the effects of different strengthening techniques for mitigating the phenomenon of progressive collapse for 2D steel moment frames. These techniques are applied to a series of moment frames of varying heights and designs using a finite element analysis involving both material and geometric non-linearities. The results of this work demonstrate that, when analysed as 2D assemblies, realistic, similar steel frame structures undergo different collapse mechanisms and that a general strengthening scheme cannot be applied to all collapse mechanisms. Verhinderung des fortschreitenden Versagens von zweidimensionalen biegesteifen