Finite Element Study On Mechanical Behavior Of Steel Frame With External Wall Panel

In recent years,with the development of urbanization and the implementation of corresponding policies such as green construction,Prefabricated buildings have developed rapidly in China.At present,The fabricated buildings of China include fabricated steel structure buildings,fabricated wood structure buildings and fabricated concrete structure buildings.Compared with others,Buildings of fabricated steel structure have the advantages of modularization,standardization,fast construction speed,recyclable resources and excellent seismic performance,which are vigorously promoted and used.However,compared with foreign prefabricated steel structure buildings,there is still a certain gap in the development of prefabricated steel structure buildings in China.The research on the prefabricated steel structure building and its supporting envelope system needs to be in-depth.In terms of the influence of the external enclosure system on the mechanical performance of the main structure,a mature theory has not been formed.Therefore,this thesis studies the effect of externally mounted light-weight concrete wall panels on the mechanical performance of the main structure through the ABAQUS finite element modeling and analysis method.The research contents and results are as follows:(1)The research scholars of domestic and foreign are summarized in prefabricated steel structure building wall plate and their connection joints,and improves the connection joints between the external wall panels and the main structure in combination with the current situation of China’s development.For a " pull-up and lower support " external wall panel connection joint,27 steel frame specimens are designed in combination with the connection joint form,the aperture ratio of the connection joint,the height span ratio of the specimen and other parameters.(2)In order to study the influence of external wall panel steel frame specimen and embedded wall panel steel frame specimen on the mechanical performance of the main structure and the failure form of wall panel,three steel frame specimens,namely one pure steel frame specimen,one embedded wall panel steel frame specimen and one external wall panel steel frame specimen,are designed,and the cyclic loading test is simulated and analyzed.It is found that the existence of wallboard improves the bearing capacity and stiffness of the main structure.Compared with the embedded wallboard,the external wallboard can weaken the influence of wallboard on the bearing capacity and stiffness of the main structure,delay the stiffness degradation rate of the main structure and protect the wallboard.(3)On the premise that the external wall panel steel frame can weaken the contribution of the wall panel to the bearing capacity and stiffness of the main structure and effectively protect the wall panel,seven steel frame specimens are designed with different connection joint forms as parameters,and the cyclic loading test is simulated and analyzed to study the influence of the external wall panel on the mechanical performance of the main structure under different connection joint forms.It is found that by setting elliptical holes for the connecting joints and changing the form of connecting joints,the contribution of wallboard to the bearing capacity and stiffness of the main structure can be further weakened,the ability of coordinated deformation between wallboard and main structure can be improved,and the damage of the structure can be delayed.(4)In order to study the influence of the aperture ratio of the connection node of the external wall panel on the mechanical performance of the main structure,five steel frame specimens were designed with the aperture ratio of the connection node as the parameter,and the cyclic loading test was simulated and analyzed.It is found that with the increase of the aperture ratio of the connecting node,the participation of the external wall panel in the bearing capacity and stiffness of the main structure is smaller,and the coordinated deformation ability of the wall panel and the main structure can be improved.(5)In order to study the effects of height span ratio,different joint connection modes and different frame story displacement angles on the mechanical properties of external wall panel steel frame,12 steel frame specimens in three series were designed and simulated under unidirectional horizontal loading.It is found that with the decrease of the height span ratio and the greater the rigidity of the connecting joints,the greater the contribution to the bearing capacity and stiffness of the main structure,the worse the coordinated deformation ability between the wall panel and the main structure,and then the damage of the wall panel becomes more and more serious.In terms of different frame story displacement angles,the external wall panel steel frame studied in this paper has good seismic performance.