الفهرس 
Chapter 1 : IntroductionOnly 14 pages are availabe for public view
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Abstract
Column loss in a flat plate building, due to punching shear, explosion, impact load or any accidental event, can lead to what is termed progressive collapse. Progressive collapse is inherently a dynamic process, which makes it difficult to experimentally explore structures with real scale. Therefore, this thesis aims to numerically investigate the behavior of flat plate systems due to column loss utilizing nonlinear finite element analysis with the aid of the computer software named ABAQUS. In this investigation, the nonlinear dynamic response of both an old flat plate building, designed according to the ACI 318-71, and a similar modern building, designed according the ACI 318-14, subjected to an instant removal of a column is examined. A cable loss in a cable-stayed bridge can lead to progressive collapse of the entire bridge. Also, because it is inherently a dynamic prosses, the progressive collapse is difficult to be accurately implemented experimentally. In this thesis, the numerical implement of both the post-tensioning and loss of stay cables was carried-out using a three-dimensional nonlinear finite element analysis; ABAQUS program. As an example, to identify the most critical cable loss scenario and progressive collapse in cable-stayed bridges, the nonlinear dynamic behavior of the Quincy Bayview cable-stayed bridge, in Illinois, USA with its main and two-side spans was studied. In addition, the effects of both the number and location of removed cables on the potential collapse of the bridge model were studied. The stay cables were represented by a 3D beam element which considers the effect of geometric nonlinearities due to cable sag. Soil scour is one of the main causes of bridge failures. Scour failures tend to occur suddenly without prior warning and are very difficult to monitor during flood events. Therefore, this thesis studied numerically the implement of the pier loss due to soil scour using a 3D nonlinear finite element analysis FEA utilizing ABAQUS package. Finally, a numerical simulation of fire condition was carried-out using a three-dimensional nonlinear finite element analysis (ABAQUS program) for a four-storey reinforced concrete flat plate building, designed according to the ACI 318-14. The modeling parameters for the mechanical and thermal properties of materials, such as concrete and reinforcing bars were included in the model. from the four cases investigated in this study, it can be concluded that robustness was the main reason for preventing or mitigating the probable progressive collapse. Robustness appeared, for example, through the usage of continuous bottom rebars to achieve ductility and tensile membrane actions. Robustness can be achieved through monolithic connections, system redundancy in order to allow for load redistribution after the loss of column in flat plate system and pier in slab- and beam-type bridge.