Push-over Analysis Of Different Kinds Of Structural System With Multi-story Steel Structure

Series of seismic destructions occurred in recent years have shown that it is necessary to perform elastoplasticity analysis for structures under strong earthquake. The method of elastoplasticity time-history analysis is regarded as a most reliable method for structural elastoplasticity analysis, but as a result of complicated calculation and poor availability, the method is not widely used. According to this, some researchers propose the method of Push-over to check the seismic ability of structure.At present, Push-over analysis has become an important part of structural seismic design, and has been concluded as one of the analysis methods for structural elastoplastic deformation in Chinese seismic design code.The developing procedure and status quo of static elastoplasticity push-over analysis is presented in this paper. Theoretic basis of Push-over method and the process to evaluate structural seismic performance is also introduced. Employing finite element analysis program of ETABS, seismic performance of three different kinds of multi-storey steel frame system (steel frame system, concentrically braced steel frame system and staggered truss system) is discussed with a comparative analysis.The curve of structural between base shear and top displacement, the location of drift angle and structural deformation curve when structural rupture occurs, appearance order and location situation of plastic hinge, the evaluation of structural response and possible failure mechanism are all listed in this paper. In addition, some other effects on the analysis results as lateral loading patterns et al. are presented. Thus the following conclusions can be obtained as: under comparison of steel frame system and staggered truss system, concentrically braced steel frame system possesses better performance of stiffness, ductility, bearing capacity in spite of dissipation ability;staggered truss system is provided with excellent restoring characteristic;plastic hinge occurs in middle part of the second floor primarily and then expends around, which works as the common failure principle of the three systems.