Vibration Control Of The Long-Span Floor Using Tuned Mass Damper

With the continuous economic construction and cultural development of China, the rhythm movements such as yoga, aerobics and sports activities are becoming an indispensable part of daily life, which makes people have more and more demand on infrastructures such as sports stadium. With the use of high-strength lightweight materials, new structure forms and large space structures, a large number of long-span floor structures have been used in public buildings such as gymnasiums. These structures have large span, light weight and low natural frequency. So these structures can easily lead to remarkably dynamic response by human activities. Although the dynamic response is not enough to result in structures’ safety problem, it will take people a sense of discomfort. That is why it is of great significance to carry out the study on the dynamic response of the structure as well as the vibration control system of the long-span floor based on human comfort.In this paper, Dalian citizens fitness center being taken as an engineering background, the third cantilevered floor vibration under human activities is analyzed, and the vibration comfort is controlled. The main research contents have been obtained as follows:(1) The evaluation criteria and design standard of the major domestic and foreign structural vibration comfort were briefly introduced. An advisable evaluation criterion was chosen for this paper by means of comparing merits and demerits of these standards. At the same time it also provides a theoretical background for the evaluation of comfort.(2) Based on the literatures, the theory of human-induced vibration was detailed described, incluing the theory of beam vibration caused by the single and the theory of floor vibration caused by the moving crowd. Through summarizing the research results of pedestrian load model at home and abroad over the years, the load model of single-step fall foot,single continuous walking, rhythmic movement was given as well as the random vibration model was formulated in the paper.(3) Comfort analysis is carried out for long-span cantilevered floor of Dalian citizens fitness center. The long-span cantilevered floor’s dynamic responses are calculated by the use of SAP2000software. The comfortableness for human in the structure is evaluated, referring to the vertical peak acceleration benchmark curve given by International Organization for Standardization (ISO). Finally, the tuned mass dampers (TMD) with the reasonable parameters are installed in the long-span cantilevered floor of Dalian Citizens Fitness Center to control the floor vibration. The dynamic analyses of structures with TMD are performed. The results are shown that the use of TMD can effectively reduce the floor vibration, make sure structure system satisfy comfort degree request, thus enhance the structure the security and the serviceability.