Study on Short-Stroke Damper Assembled in Tuned Mass Damper
|關鍵字:||調諧質量阻尼器;短衝程阻尼器;最佳化設計;阻尼器衝程;Tuned Mass Damper;Short-Stroke Damper;Optimal Design;Damper stroke|
The damper stroke and the mass stroke are the same for currently used conventional TMD, therefore, a long-stroke damper is required for engineering applications. In addition, a considerable space for the damper stroke is reserved in the design. Due to the high-accuracy requirement for manufacture of long-stroke damper, higher technology is requested. Besides, higher budget and the difficulty for maintenance are issues for long-stroke damper as well. According to the above features, a “Short-Stroke Damper assembled in Tuned Mass Damper (SSD-TMD)” is proposed in order to reduce the damper stroke of conventional TMD. The stiffness of SSD-TMD is separated into two parts. The first part is connected in parallel with the damper. Furthermore, the paralleled system is connected in series with the second part of stiffness which is further attached to the mass block. The assemblage will produce a different stroke between the damper and mass in order to significantly mitigate the damper stroke and solve the difficulties for both engineering applications and design. In this article, the model of SSD-TMD is firstly proposed. The design parameters of SSD-TMD is proposed following the optimal design parameters for conventional TMD. By using the Direct Search Method, the optimal deign parameters of SSD-TMD, optimal stiffness factor and optimal damping coefficient factor, will be able to determine. After that, the vibration reduction ratio, damper stroke ratio and mass stroke ratio of SSD-TMD to conventional TMD are further determined. By using curve fitting and the regression method, the optimal design formulae for a single degree of freedom (SDOF) structure implemented with SSD-TMD are defined. Finally, by a case study of Taipei 101, three different kinds of system: SDOF structure, SDOF structure with conventional TMD, SDOF structure with SSD-TMD, are compared by characteristic analysis, frequency response function and time history simulation, respectively. In addition, the sensitivity analysis of stiffness factor and damping coefficient factor is carried out. The results show that SSD-TMD can significantly reduce the damper stroke. Besides, both effectiveness of vibration reduction and mass stroke for SSD-TMD with suitable design can be better than the conventional TMD. However, the damping force of SSD-TMD is greater than the conventional one.