Nonlinear Dynamic Elasto-plastic Time History Analysis Of Prefabricated Steel Frame Structure With Inclined Support Joints

At present, the application of prefabricated steel structure is more and more widely, its main components are producted in factory and installed directly on the site of the project. It has short construction period and high efficiency while it can save the amount of field operations. The development of prefabricated steel structure is matched with the housing industrialization development of national strategy, and it caters to the theme of energy saving and environment protecting in the current. It is a proper structure form of economical society. The prefabricated steel frame structure with inclined support joints is a new type of prefabricated steel structure system, which has a bright market future and application value. But the dynamic response of these new structural system under earthquake are unknown. Therefore, the detailed seismic performance analysis of the prefabricated steel frame structure with inclined support joints becomes more and more important.Based on a prefabricated steel frame structure with inclined support joints, this thesis mainly conducts to study the structural performance of it under the severe earthquakes. The specific content is as follows:(1) After introducing the theoretical analysis of structural seismic and the history of the prefabricated steel structure, the thesis describes the characteristics and advantage of these new structures.(2) It introduces the theoretical basis of elasto-plastic time history analysis, which includes elasto-plastic finite element model and elasto-plastic time history analysis methods. Elastic-plastic finite element model is divided into three categories: based on the model, based on the section of the model and model based on components, there are also differences between the contact. It introduces how to choose the seismic wave reasonably by seismic intensity index.(3) The elasto-plastic time history analysis method was conducted to the prefabricated steel frame structure with inclined support joints and the prefabricated steel frame structure without inclined support joints under the severe earthquake. The results suggest that the overall stiffness of structure increases greatly because of the inclined support joints and the deformation is reducing under the 7 degree earthquake and the top joint displacement of the structure is reduced to 56.6% while the maximum interlayer displacement angle is reduced to 61.3% in artificial waves, most of the plastic hinge appears in the weds of the truss girder and the columns are in elastic stage.(4) The prefabricated steel frame structure with inclined support joints is a new structural system, the choose of some parameters in analysis will have a great impact on the results. In order to consider the influence of these factors reasonably, based on the structure, it analyzed the influence of the seismic wave input dimension, gravity P-Δ effect and damping ratio in the elasto-plastic time history analysis of prefabricated steel frame structure with inclined support joints.