Research On Antiseismic Strengthening Of Reinforced Concrete Frame Structures Based On Displacement

China suffers earthquake disasters frequently, and earthquake caused a great threat to people's lives and properties for a long time. With the continuous renewal of a code for seismic design, intensity of Seismic fortification was improved in some areas. A large number of buildings near a service deadline. For these reasons, some buildings suffered earthquake. There are a lot of RC frame structures which need seismic strengthening. However, from some of the earthquake disasters and experimental studies in recent years, it shows that the collapse of buildings, mainly due to the energy dissipation capacity and plastic deformation capacity of structures, do not meet a desired ability of structures. The antiseismic design that bases on bearing capacity of structure cannot be guaranteed to achieve a desired plastic deformation or ductility requirements of structures. Meanwhile, with individuation is attached significance to buildings of owners, so many different building objective performances need to be achieved. Therefore, Antiseismic strengthening designs of the RC frame structures based on displacement were proposed.The paper focuses on the energy dissipation capacity and plastic deformation capacity of structure in earthquakes. Solutions of pushover are used to analyze structural seismic performance evaluation, also there are relevant seismic strengthening design theory and procedures that will be discussed. The main research contents include:(1) Among many parameters of the seismic performance evaluation, in this study use an inter-story displacement angle as the quantitative index of structural performance level. According to the structural limited state under earthquake, it should divide the structural performance into three levels and combine it with three seismic fortification levels in seismic design code. Finally, it will get the structural objective performance.(2) Using Sap2000 finite element software to establish an existing RC frame structure model, and it can go through the pushover for structural seismic performance evaluation. The most inter-story displacement angle appears in variable cross-section of frame column. The plastic hinges firstly appeared at column base of bottom columns. Generally, structural weak story appearance usually is located near the frame column variable cross-section, and bottom columns' column basis are weak points of structure.(3) In this paper, the antiseismic strengthening design steps of RC frame structures are proposed, which based on displacement. Composite fiber reinforced polyme reinforcement and bonded steel reinforcement are used to Strengthen existing RC frame structure. Structural Plastic Deformation in different seismic fortification levels has been effectively controlled.(4) Based on the principles and analyze projects of two kinds of reinforcement, the effect of reinforcement externally bonded steel reinforcement method by the material thickness greater impact. Therefore, when structural reinforcement design, if the inter-layer structural displacement angle less than limit, a little reinforcement structure to meet its target performance requirements, the choice of easy construction, low cost composite fiber reinforced;On the other hand it should be used reinforcing effect is more obvious, but the construction of complex, higher cost of steel reinforced outer sticky.