Progressive Collapse Analysis And Mechanism Study On Prefabricated Steel Frame Structure With Inclined Support Joints

Prefabricated steel frame structure with inclined brace joints is a new type of structural system put forward in recent years, instead of traditional architectural structural pattern, it use steel instead of concrete, brick and wood, etc., can well realize the standardization of design, the industrialization of production and the assembly of construction. Although some domestic colleges and R&D institution carried out an in-depth research on the issue and achieved fruitful research achievement, but it still lack of progressive collapse analysis that aim at the structural system, research that based on ABAQUS substructure method is further scarcely,therefore, this paper selects simple framework and establishes finite element model to verify the ABAQUS substructure analysis method, compares the difference between the overall model method and the substructure method, the pole unit and the entity unit, the static analysis and the dynamic analysis. Based on this method to make an research on a particular instance of engineering to study the dynamic characteristics of progressive collapse, evaluate its progressive collapse resistance and analysis the failure mechanism of progressive collapse on prefabricated steel frame structure with inclined brace joints.The main content of this paper include:(1)Research the progressive collapse assessment method at home and abroad,according to the characteristics of engineering and the substructure method of ABAQUS, this thesis select reasonable analysis method and establish a collapse criterion that conform to the requirements of the project.(2)Combined with ABAQUS substructure analysis method theory, this thesis establishes a substructure selection methods and the scope of admissible collapse, and build a simple verification model to verify the feasibility and accuracy of ABAQUS substructure analysis method in the analysis of progressive collapse of the structure,and provide a reference basis for subsequent analysis.(3)According to the practical engineering project profile, this thesis establishes a finite element analysis model and determine an reasonable way of loading on the structure to make a structural progressive collapse dynamic nonlinear analysis.Research displacement response ? internal force distribution and energy change of components that focused on in the process of dynamic analysis, and evaluatethe progressive collapse resistance of the engineering.(4)This thesis selectes a common framework includes invalid column in analytical model for stress analysis, studies the internal force redistribution mechanism, the plastic zone distribution mechanism, internal force redistribution of rotating hinge mechanism and sliding surface mechanism.(5)Summarize the research content of this thesis, put forward design Suggestions for prefabricated steel frame structure with inclined brace joints according to the results and prospects follow-up work of the research.