Numerical Simulation On Progressive Collapse Of Steell Frame Structures

In recent years, with the development of Chinese economy, as China's economicdevelopment, steel frame structure is used more and more in large constructions. Suchnon-predictable and unexpected events as the explosion, collision, fire and so on arebound to cause direct damage to the structure's local components, which may causesteel frame system to collapse, resulting in a heavy continuity casualties and hugeeconomic losses. In view of the above reasons, it is of great practical significance tostudy and analyze progressive collapse process of the steel frame structures.This paper selects a two-story steel frame structure system as the research objectand uses the finite element analysis software to analyze structure's progressivecollapse process after the destruction of some possible vertical load-bearingcomponent part, in order to find the methods of resisting progressive collapse andcontroling the space form.Based on the international design specifications on resisting progressive collapse,this paper summarizes the practical application of the related design methods ofprogressive collapse-resistance such as he specific local resistance method, theindirect design method, the alternate load path method. And it adopts alternate loadpath method to undertake dynamic analysis after the study of progressive collapsesimulation.This paper determines a reasonable constitutive parameter in order to establish areasonable three-dimensional finite element model. The numerical simulation of planeframework, a space frame without concrete board and a space frame with concreteboard are obtained respectively in this paper. According to the assumption of differentstructure system initial damage position, it sets up different operating condition ofremoving the damaged components, and uses ABAQUS/Explicit to study the dynamicresponse of the residual structure. Each vertical bearing component part and board'scatenary's effect have the influence of the ability about resisting progressive collapse.Finally this influence is verified effectively in this paper. During the process of removing the column by using alternate load path method,whether there is a structure progressive collapse depends on whether good newbalance of internal force redistribution can be achieved. For the operation conditionwhich occurs the progressive collapse, this paper describes the time and sequence ofeach component's collapse to specify and visualize the structure's progressive collapsewhich provides sound evidence to identify the relevant component which plays a keyrole in progressive collapse. Finally, in order to improve the ability of resistingprogressive collapse, this paper puts forward some effective measures and methods tocontrol the occurrence of accidental events.