Research On Mechanical Properties And Optimization Of Concrete Filled Steel Tubular Frame Structure

Because of the advantage of high bearing capacity and good ductility, concrete filledsteel tubular structure becomes the main form column component of high frame structure.In order to develop need energy and land saving house. research on optimization ofconcrete filled steel tubular frame structure is necessary. It is helpful to optimizie theproperties of structure and saving the steel and concrete.In this paper, based on a practical project of concrete filled steel tubular framestructure, study on optimize and analyse were carried out. Using PKPM structural designsoftware and genetic algorithm to optimize member section and check the whole modal.Firstly using PKPM structure design software to analyse the original structure and extractthe original structure internal force.Second, the genetic algorithm optimization constraintsare internal force and standard control condition and the component cost most savings istarget function, genetic algorithm optimization is done by adjusting the related parametersto optimize the beams and columns. Then artificial process the optimized cross-sections inthe premise of ensuring cross-sections meet the structural requirements. Reassemblingbeams and columns back to structure to check the components and the whole modal byPKPM structural design software. Repeat above process until finally the optimizedstructure meets the provisions of the structural design specification requirements. As aresult, steel consumption of beam reduced from331.5t to250.93t saved24.3%. Steelconsumption of column consumption reduced from232.54t to145.51t saved37.4%.In the ABAQUS finite element analysis, C3D8R element is used to simulate steel andconcrete, the mechanical properties of one piece of optimized concrete filled steel tubularframe structure are discussed. The analysis result shows that (1) under the load of deadload, live load and wind load, the concrete filled steel tubular frame structure materialshave not reached the plastic state; the whole modal meets the control requirements of thespecification.(2) In seven degrees seismic loads, the displacement between1and2layerof concrete filled steel tubular frame structure exceeds the limit of the specification requirements, the other floors layer displacement meets the specification requirements. theconcrete filled steel tubular frame structure appears large structure offset, boundaryColumn’s stress increased significantly.Displacement between1and2layer of concretefilled steel tubular frame structure with shear wall in bottom does not exceed the limit ofthe specification requirements, the other floors layer displacement meets the specificationrequirements, and concrete filled steel tubular frame structure with shear wall in bottomdoes not appearance large structure offset, boundary column’s stress increased notsignificantly.(3) In the top of structure, Column and beam of frame structure with shearwall and frame structure stress are small. In the middle of structure without shear wall,there is an obvious stress concentration area in the node of beam and column. In the middleof concrete filled steel tubular frame structure with shear wall, there is no obvious stressconcentration area in the node of beam and column.