Seimic Performance Of Concrete Framestructure With Adding Light Steel Stories

Due to the rapid growth of economy and population in China, the urban land is becoming increasingly tense in recent years. At the same time, a large number of old buildings, which can still be used, are unable to meet the immediate use of functional requirements. Adding light weight stories is being gradually extended in the building renovation process for its advantage of light weight, flexible layout, low cost, easy construction. This excellent additional layer structure form has been widel y used in structure reinforcement, which has achieved good social benefits.However, the design of adding light weight stor y is still not perfect. In many cases, engineers only calculate adding layer portion. Besides, the consideration on the seismic performance of overall structure is limited. Indeed, light weight story added on concrete structure exist many problems, such as the overall structure of the mass and stiffness vertically unevenly distributed, the trend of forming weak layer, the choice of hinged connection and ringed connection between the old portion and the new one, and the different damping ratio between concrete and steel structure which is hard to determine. These problems make the seismic performance of the concrete building s with adding light weight stories cannot be effectively guaranteed, which limits the further application of this structure form.Combined with the actual project, the thesis studies the seismic performance using different softwares. The research includes the following:(1) The actual project site testing, inspection status of the building, induction of the engineering and structural design information.(2) The static and dynamic analysis of the original RC structure and the concrete structure with adding light steel layer was finished using PKPM, and the comparison of different design methods was focused on.(3) Using the finite element software SAP2000, the 3D model of the whole structures was improved. The time history analyses under small and major earthquake were completed. Finally, the deformation characteristics and design suggestions of this kind of structures were summarized to provide the detailed considerations for the future seismic design.