| With the continuous development of the economy and society, the structure form and use requirement of building are developing rapidly towards large span structure. The seismic problem in civil engineering design is always a crucial procedure of stucture safety, especially the high-rise building structure.The traditional architectural structure seismic method takes “hard resistance” as the main approach through enhancing the structure stiffness, quality and section size, which all increase the cost of construction, however, the damping effect is questionable. Structure vibration control, especially the passive control, as a novel method of earthquake resistance, is used more and more widly in the structural seismic resistance of high rise building due to its advantage of relatively well-developed theoretical basis and reliable control effect.A novel passive energy dissipation system, the Tuned Rotary Mass Damper(TRMD),based on the hollow floor is proposed. The TRMD adopted in this paper is composed of a spherical vibrator and arc-shaped slide. One or more TRMD are setting in the spare room of two-way ribbed hollow floor in advance. The main structure subjected to earthquake excitation begins to vibrate which leads the movement of vibratot. Therefore the energy input of the structure from dynamic loads could be absorbed through the rolling motion of the vibrator and dissipated through the friction between the surface of the ball and the path, and it can also take full advantage of the empty room of hollow floor.Specifically, the equation of translational motion of a single-TRMD-dissipation and multi-floor-TRMD-dissipation system are derived by the Lagrange's variational method, with the later based on the small-amount assumption of slope displacement. Then,numerical simulations of controlled system are implemented to analyse the effect of TRMD. Results indicate that TRMD can effectively reduce the peak displacement and energy amplitude of the seismic response of structures to different earthquake accelerations. Further, the application range of small-amount assumption should be less than 1 rad through comparison, and the relationship between the damping effect of TRMD and the seismic accelerations amplitude is also discussed. With regard to the multi-floor-TRMD-system, it is analysed based on the small-amount assumption from the five layout plans of ground floor, top floor, each floor, alternating floor and top three floors of TRMD. The results of numerical simulations turns out the layout plan of top floor is the best, while ground floor is the worst, and the damping effect of TRMD is different sujected to different earthquake accelerations. Further, the seismic analyse of multi-TRMD-controlled structure is also discussed based on top floor layout of TRMDs with the same parameter. It shows that the bigger of the value of n, the smaller of the peak diaplacement of TRMD, however, it is at the expense of reducing the effect of earthquake resistanse.Since the earthquake has obvious stochastic characteristics, it is necessary to investigate the random dynamic response of the damper system. Specifically, the random dynamic analysis of single-floor and muli-floor controlled system are discussed using Monte Carlo simulation and statistical linearization method based on the models of stationary white noise and Kanai-Tajimi respectively. The numerical results shows that TRMD can not only effectively reduce structural static displacement standard deviation, but also greatly shorten the time of structure to achieve steady. Meanwhile, the computed results of the two methods are consistent under the certain premise of calculation accuracy, and the statistical linearization method can improve the computational efficiency of random vibration analysis significantly which lay a foundation for parameter optimization of TRMD. Promising agreement using statistical linearization method between the analitical integration and numerical integration is observed. |
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