Research On Deformation Control Design Method For High-Rise Steel Frame Structures

Compared with the traditional method of calculating length,direct analysis design method can directly get the structure bearing capacity and deformation performance of the whole,without the need for the various components of structure strength and stability calculation.At home and abroad about the direct analysis method research has focused on how to consider various nonlinear factors influence the ultimate bearing capacity of the structure.But studies have shown that the bearing capacity limit state design framework,high soft steel structure pillars lateral often beyond the limit of structure normal use limit state,the actual bearing capacity of structure is controlled by the structure deformation of the performance.According to the above problem,this paper has carried out the following work:The steel structure design process for three spans thirty-two layers braced frame structure has been studied in detail,in which the method of first order elastic analysis,the approximate second-order elastic analysis as well as direct analysis method.Using the different design methods above,the ultimate capacity,internal force and deformation performance for structures have been analyzed comparatively.Research shows that the structure of the whole process of direct calculation method for ultimate bearing capacity should be a lot higher than the first order elastic analysis,because the direct analysis method can consider the plastic redistribution,give full play to the performance of the material,not cause waste of materials,make a design more economic and reasonable.Modal analysis in ANSYS finite element software and the function of the eigenvalue buckling analysis and its calculation steps,and two spans twenty layers,three spans six layers and three spans thirty-two layers steel frame-support structure modal analysis and the eigenvalue buckling analysis.In modal analysis,considering the national standard of the different initial geometric imperfection and support in the impact on the natural frequency of the structure,found that the initial geometric imperfection and support decorate a form to a little effects on the natural frequency of the structure,but the presence of support evident effect on natural frequencies.Steel frame supporting structure of three spans thirty-two layers eigenvalue buckling analyses,and adjust the computing scheme of the eigenvalue buckling analysis,eigenvalue buckling analysis can simulate the structure of the initial geometric defects and structure in the case of buckling deformation.Steel frame structure of the three spans six layers and steel frame structure under low cycle loading hysteretic performance analysis,through the calculation of hysteretic curve and skeleton curve,can analyze the structural stiffness degradation,ductility and energy dissipation capacity.Around the second-order effect parameters using finite element program ANSYS second-order influence parameter,which are the depth-width ratio,column slenderness ratio and general stiffness ratio of beam to column,for twelve to thirty layers of steel frame structure and twenty to forty layers of working condition of steel framework-support structure design and parameter analysis.For steel frame structure and steel frame supporting structure under low cycle loading load of hysteretic performance analysis,comprehensive evaluation of various parameters on the influence of structural seismic performance.It was found that the ratio of framework second-order effect coefficient of little influence on the performance of the energy consumption of steel framework,but the second order effect coefficient of steel frame supporting structure has great influence of energy consumption.The lateral displacement limit of high-rise steel structure under horizontal load is analyzed,and a direct analysis design method based on displacement is put forward under low cyclic reciprocating load.Two different design methods based on the limit state of the bearing capacity and the limit state of the normal use are compared and the applicability of the direct analysis method based on displacement as the control criterion is verified by an example.