The Application Of Buckling-restrained Brace In The Light-weight Steel Storey-adding Structure

Since the reform and opening up,some old low layer or multi-layer architecture although has been unable to meet the needs,for example,the function of people’s production and life,but it can not be a simple and brutal demolition,instead the need to implement the reinforcement of housing,the modification of light steel layers is widely used because of its short construction period,low cost,and high efficiency.After the layer is added,the seismic performance of the structure changes.On the one hand,the overall structure becomes softer and the cycle increases;on the other hand,the quality and rigidity of the light steel part and the original structure are abruptly changed.Therefore,it is necessary to reinforce the building after adding layers.As an emerging reinforcement method,the buckling energy-dissipation support not only can reduce the flexibility of the structure and improve the bearing capacity,but also can consume most of the earthquake effect due to its own energy-consuming capacity,As the first protection line in the structure,ensure that the main structure meets the earthquake-resistant seismic requirements.This article takes the reinforcement project of the teaching building of the Jiuli Middle School in Fuyang as an example.For the problem that the layered structure does not meet the seismic requirements,the buckling-restrained brace reinforcement scheme is adopted so that the building after the additional layer can be put into use safely.The main research contents as follows:Firstly,the relevant knowledge and component models of buckling-restrained brace are systematically introduced as the theoretical basis for Energy-consuming support reinforcement design.Through the analysis of the original structure after adding layers,it is known that the seismic performance of the structure after adding light steel layers Do not meet the requirements,under this premise of the structure after the addition of two design layout of buckling-restrained brace,and analysis and comparison.Secondly,the modal analysis and the moderate decomposition response spectrum analysis are performed on the layered structure.From the analysis results,it can be seen that the two energy-consuming support arrangement schemes can effectively reduce the flexibility of the structure,improve the resistance to lateral stiffness,avoid the problem of stiffness ratio mutation,effectively reduces the inter-layer displacement angle of the structure and controls the adverse effect of the torsion on the structure.Thirdly,using the finite element software to perform nonlinear analysis on the three models after layer addition,including Pushover analysis and nonlinear time-history analysis.Through analysis,it can be concluded that in all three models,model 3 is supported by full-layer layout.Therefore,the displacement angle between layers of each layer is minimized,which effectively reduces the inter-layer displacement of the structure and ensures the safety of the structure.Under rare earthquakes,energy-consuming supports share most of the shear force of the main structure.And the energy-consuming support takes precedence over the plastic hinge of the main structure,which protects the main structure from entering the plastic stage too quickly.Therefore,the energy dissipation support has a good protection effect on the main structure.Finally,the analysis of the axial force of the energy-consuming support under the rare earthquakes further confirmed the conclusions obtained in the previous article.The connection mode of energy-consuming support nodes is also given to ensure that the energy-consuming support can work well with the main structure.The article concludes with a detailed summary of the research content and deficiencies of the full text.