Seismic Retrofitting And Damage Analysis Of Frame Structure With Mild Steel Damper

ABSTRACT:The use of energy dissipation method for seismic strengthening of existing buildings is a new trend in recent years, by adding energy dissipation device to the structure, this approach can modify the seismic response of structures and mitigate the effects of seismic forces, which has been widely concerned. Steel damper added stiffness with diamond openings has simple structure, definite damping mechanism, and it has a certain theoretical basis in China, but there is little research and application in the practical engineering with this kind of damper.This paper summarized the research status of this damper, Review the calculation method of damage analysis, and has a made a comprehensive study on the energy dissipation structure based on this damper from the calculation model to analysis method. The main research contents of this paper are as follows:1) Numerical simulation and parametric analysis are used to steel damper added stiffness with diamond openings by using the ANSYS finite element analysis software, in-depth study of this damper has done to research on its hysteretic behavior, and analysis the effect on the mechanical properties by the different geometric parameters.2) Introduces a engineering example which is a reinforced framework using this kind of damper, a nonlinear calculation model of three-dimensional structure has been Established by using SAP2000finite element analysis software, and introduces its’lumped plastic hinge model and macro model of the damper by using Bouc-Wen differential equations.3) Introduces the time history analysis results of the structural model under frequent earthquake and rare earthquake, and evaluate the seismic performance of existing structure and the damping control effect by using this kind of damper.4) Carries on secondary development based on SAP2000API, two plug-ins for calculating the members’damage index based on Park-Ang damage model have been produced, which effectively improve the efficiency of data processing in complex space model, structural damage index has been calculated by using weighted combination method, which is used to verify the damping control effect by using this kind of damper.5) Finally, summarize the full paper, give some suggestions in engineering application, and prospect the future research.Practice shows that, in the theoretical principle of boundary conditions, this kind of damper has stable plastic hysteretic behavior and energy dissipation capacity. For seismic reinforcement by using this damper device, in the best case scenario, it can give full play to its hysteretic energy dissipation capacity, achieve good damping effect of reinforcement.