Study On The Influence Of Seismic Performance For Diagrid Tube Structure With Buckling Restrained Braces

China is at the junction of the Pacific Rim seismic zone and the Eurasian seismic zone,causing frequent earthquakes.As a new type of structural form,diagrid tube structure has strong lateral stiffness but insufficient structural ductility.It is prone to brittle failure under the action of large earthquakes.Structural ductility can be increased by replacing common columns with buckling restrained braces.In this paper,the SAP2000 finite element calculation software is used to evaluate the structural model by Pushover analysis method,elastoplastic time history analysis,incremental dynamic analysis method(IDA)and seismic vulnerability analysis to assess the seismic behavior of buckling restrained braces.Consider the influence of corner column and aspect ratio on the seismic performance of the two structures.The main research results are as follows:(1)The ductility factor is used to determine the ductility of the structure and to assess the seismic performance of the diagrid structure.The diagrid structure that sets buckling restrained braces can improve ultimate lateral bearing capacity and structural ductility obviously of the common diagrid structure.(2)The diagrid structure that sets buckling restrained braces and the common diagrid structure can improve ultimate bearing capacity and structural ductility slightly by setting corner column.As the aspect ratio increases,the ductility of the diagrid structure that sets the buckling restraining braces is significantly reduced.(3)The diagrid structure does not enter the nonlinearity at the 8 degrees fortification earthquake.The seismic response of the diagrid structure that sets buckling restrained braces and the common diagrid structure is basically the same at the 8 degrees fortification earthquake.The larger aspect ratio the diagrid structure that sets buckling restrained braces has,the faster the plastic energy consumption.(4)The failure probability of the diagrid structure that sets buckling restrained braces is significantly reduced in each limit state compared with the ordinary diagrid structure.The increase of the aspect ratio makes the diagrid structure that sets buckling restrained braces weaken the seismic performance of the buckling restrained braces.