ELASTIC-PLASTIC DYNAMIC ANALYSIS OF COLD-FORMED THIN-WALLED STEEL FRAMING SYSTEM OF LOW-RISE RESIDENTIAL BUILDINGS WITH COMPOSITE WALL

The seismic behavior of the cold-formed thin-walled steel framing system of low-rise residential buildings is essential for their wide application. A numerical model was developed to simulate the performance of this type of structures using ANSYS. The steel members and the holes at doors or windows with or without the stiffened ribs, and the frames with or without composite walls were considered. Static and elastic dynamic time history analysis were performed under frequent earthquake based on the design earthquake intensity 7, and elastic-plastic dynamic time history analysis was performed under rare earthquake based on the design earthquake intensity 7, 8 and 9, respectively. It is shown that the elastic story-drift of the structure was determined by the wind loads mainly under the loading combination with frequent earthquake action, and the elastic-plastic story-drift was determined by the loading combination with rare earthquake action. There are singificant differnence in the bearing capacity, deformation and seismic performance of the structural system with or without the composite walls. The maximum elastic-plastic story-drift of the structures was satisfied with the requirement of the current design code under rare earthquake in general. The type of structural system with OSB composite wall and stiffened corner columns exhibited excellent seismic behavior. This paper provides reference to further research on seismic performance and practice of this type structures.