Study On The Damper And Damping Ratio For Vibration-absorption System Consisting Of Infilled Wall And Frame Structure

Infilled wall frame structure is a form of widely used building structure at the present stage in China. In the earthquake of 5.12 Wenchuan, this kind of structure was severely damaged, causing major property losses and casualties. So under the restrictions of China’s national and economic condition, it is necessary to seek a safe, economic and effective shock absorption design method.Using the principle of tuned mass damper(TMD), vibration-absorption system consisting of infilled wall and frame structure makes the infilled wall as the mass damper to reduce the seismic response. In this way, without attaching another mass to the main structure vibration-absorption system has already been formed. The U-shaped metal damper is used as an energy dissipation device in the vibration-absorption system. Therefore, vibration-absorption structure of composite infilled wall frame achieves the goal of shock absorption through dynamic vibration absorbing and damping energy dissipation. The study completed by this paper is as followed:(1) As for the U-shaped metal damper adopted by vibration-absorption structure of composite infilled wall frame, the theory calculation formula of yield strength, yield displacement and the initial stiffness was deduced with the mechanics model simplified based on simplified constitutive mode.(2) The U-shaped metal damper was simulated under the static and cylic loading by the finite element software ABAQUS. By comparison of the numerical simulation results, the yield force errors of the theoretical formula calculation results are less than 5% and the initial stiffness errors of that are within 5% in addition to the specimen U3. This suggests that the results of the theoretical formula are reasonable. According to the results of numerical simulation, the hysteretic energy dissipation properties of the damper was analyzed and provided certain basis for the value of U-shaped metal damper.(3) Vibration-absorption structure of composite infilled wall frame and ordinary infilled wall frame structure was conducted modal analysis by using the finite element software ANSYS with different damping ratio respectively under the conditions of three stiffness coefficient for substructure. Afterwards the results of the modal analysis were analyzed by comparison with the modal of hammer test.(4) After the modal analysis, structures under various operating conditions were conducted dynamic time history analysis by using the finite element software ANSYS. Based on decreasing amplitude ratio and time history curve of the displacement and acceleration of the top, the influence of damping ratio on the damping performance was studied.