| There is an important basis for performance-based seismic design, namelyseismic performance analysis. In order to better reflect the behavior-based seismicdesign philosophy, with an accurate grasp of the structure of the performancecharacteristics of the elastic-plastic stage, using reasonable structural responsequantitative indicators to assess the states of the structure under seismic action ofdifferent level is a necessary means to fine design and considerations for modernbuilding structures. A proper way to quantitatively describe the degree of structuraldamage in the earthquake is important for post-earthquake reinforcement andmaintenance. In fact, due to the different degrees of damage to the structure, theparameters of the structure is nonlinear and time-varying, especially the stiffness ofthe structure can be understood as changed by the damage. So from a macroperspective, structural damage can be solved in accordance with the structuralparameters change.In this paper, by gradually increasing the level of the force (to analog externalload) to change the dynamic characteristics of the structure, structural damage isassessed. Changes of the frequency are proposed as calculation model for thestructural damage index. Firstly, determine the frame column "Shear-displacement"elastic-plastic curve for every layer, structure and load are established as numericalmodel in MATLAB software. Using pushover analysis method, five-story framestructure is analyzed under different working conditions. The relationship betweenchanges in dynamic characteristics is studied through the process.In this paper, the damage index proposed based on frequency of can show a cleartrend, that the frequency change can clearly correspond to the structural damage.Extracting stiffness matrix through the calculation process shows that increaseddamage index are associated with floor lateral stiffness degradation clearly. This paperprovides a new way for the overall structure damage assessment. |
PDF Full Text Request