Vibration Suppression of Building Installed with Simple Pendulum Tuned-Mass Dampers

• Main Authors: Li, Jhih-Lun, 李至侖
• Other Authors: Huang, Li-Jeng
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/77181747097850903103

碩士 === 國立高雄應用科技大學 === 土木工程與防災科技研究所 === 98 === Taiwan is located at the Pacific Seismic Ring so that earthquakes usually occur which induce a lot of disasters and collapse of buildings and thus how to increase the aseismic capacity of a building is important for structure engineers. In recent years various passive and active anti-earthquake technologies have been promoted but the cost of them are too high to be employed widely. This thesis is proposed to develop a newly vibration suppression system for buildings using simple pendulum type tuned mass dampers (SPTMD) and theoretically analyze the dynamic responses and oscillation suppression of buildings during various external dynamic loadings. Lumped mass models are employed to build up the dynamic models of building uninstalled and installed by different types (top level of single-storey, top level of two -storey, bottom level of two-storey, both level of two-storey etc.) and the dynamic equations are derived by both Newton’s and Lagrange’s equations and then expressed in state space form and finally the dynamic responses are computed by fourth-order Runge-Kutta algorithm. The effects of various parameters on vibration suppression for different dynamic excitations (such as free vibration, unit-step, harmonic loading, El Centro ground acceleration, etc.) are all studied in detail. Numerical results show that the SPTMD system can be employed to reduce the frequencies, increase the periods and suppress some dynamic responses of buildings. Among various installation types the ones installed at top level are the best and in such cases the suppression of accelerations is the most effective. Parameter study depict that all design factors including masses of the ball and bar of pendulum, damping coefficients, spring constants and length of pendulum are all important. The larger of the damping constants and the length of pendulum, the smaller of dynamic responses of building are obtained. WhileηBi=0.5, ηRi=0.005, ζRi=0.25, ζθi=0.25, li=2 and si/li=0.5 seems to be the better values for SPTMD installed on top level of single and two storey buildings. However, it is better when κRi&κθi are 0.5 and 0.25 for single and two story cases, respectively.