Study On Earthquake Collapse Failure And Influencing Factors Of Space Steel Frame

If the structure is damaged under a strong earthquake load,will cause serious casualties and property damage,steel structures have a good performance in resisting earthquake damage,but the collapse of steel structures has also occurred,the main reason for this phenomenon is due to the lack of understanding of the mechanism about structural collapse failure,and the relevant collapsing failure criterion does not accurately reflect the characteristics of structural collapse.In this paper,the finite element analysis model of space steel frame structure is established by using LS-DYNA,The failure process of the structure under earthquake load is studied,mainly involves the following work:(1)Introduce the background of the research topic,summarize the research status of the earthquake collapse problem from different aspects,points out that there are shortcomings in the standard of structural collapse.Introduces the method of structural collapse and failure analysis,selects the time history analysis method as the research method.(2)A fine finite element model of six-layer steel frame structure was established by software LS-DYNA,then introduces the selection method of model related parameters and the selection and input method of seismic records,the correctness of the finite element model is verified,ensure the effectiveness of the analysis below.(3)The dynamic response of the space building with the floor under strong earthquake load is simulated and analyzed,the damage evolution process and collapse failure mechanism of this type structure are obtained.Based on the data processing results,the failure mode and cause of the strong earthquake damage about the frame structure are analyzed,and the failure criterion of the strong earthquake in the building structure is reasonably assumed.(4)Based on the simulation of the collapse process of the strong steel frame structure,the influence of different influencing factors on the collapse of the structure is studied,such as floor,floor number and axial compression ratio.Analyze the difference about the collapse mode between the pure frame structure and the structure with the floor,explores the influence of the floor on the collapse of the structure.At the same time,the collapsing failure process of different axial compression ratio and floor number structure is analyzed to explore the effect of axial compression ratio and floor number on the collapse of structure.