الفهرس 
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Abstract
Progressive collapse is defined as a local failure that might cause the building to be severely damaged or entirely collapsed. In the United States both General Service Administration (GSA) and Unified Facility Criteria (UFC) have produced two different criteria for the design of new buildings and checking the safety of existing buildings against progressive collapse.
The main objective of this report is to compare the linear static analysis method for a multi story building with nonlinear dynamic analysis method. Both methods are suggested by the GSA guidelines. The building used for analysis was designed, according to the Egyptian code, for gravity loads only or for gravity and lateral earthquake loads. In addition, the effect of using partial bracing members in the first floor to avoid the successive failure was studied.
In the analytical study, a seven story height building with three bays in x¬direction and two bays in y-direction was studied. Linear static as well as nonlinear dynamic 3D model were implemented using SAP2000. The nonlinear dynamic analysis was performed using a nonlinear time history analysis.
The results obtained were categorized into two groups. These obtained from the static analysis were compared with those obtained from the 110nlinear dynamic analysis for both braced and unbraced case. The braced building showed a better behavior in preventing progressive collapse than the unbraced building. Besides, the building designed to sustain seismic forces showed less probability to progressive collapse. Deformation, maximum moments and axial forces in members obtained from the model results were discussed.
For the studied cases, it was concluded that designing the building to sustain earthquakes provides adequate strength and ductility which will lead to minimizing the risk of progressive collapse. Adding bracing to the perimeter of the first floor will enhance the structure behavior against progressive collapse. The conclusions are limited to the assumptions of the analytical model.