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Information × Registration Number 0224U001624, 0122U001336 , R & D reports Title Development of the theory and methods of analysis of vibration processes in complex deformable systems under operational loads of periodic, stochastic and shock character popup.stage_title Head Lizunov Petro P., Доктор технічних наук Registration Date 26-01-2024 Organization Kyiv National University of Construction and Architecture popup.description2  The problem of undesirable vibrations mitigation of the forced constructions was studied at the reporting stage. Two decades ago, a mechanism for passive vibration control and reducing was introduced. The Tuned Mass Dampers with linear connection to the main structure have been successfully used in a number of known high-rise structures. As their development new passive vibration control devices Nonlinear Energy Sinks, were proposed. These devices have a nonlinear connection to the main structure; due to the nonlinearity of the system, deformation of the main structure decreases. The vibro-impact sink is considered as one of the most effective and is studied at the reporting stage. It became clear that its parameters must be optimized to guarantee its efficiency. We were able to find optimal damper parameters that ensure reliable and stable attenuation of the main structure vibrations over the entire range of the exciting force amplitudes and in a wide range of its frequencies; the resonance peak has also been reduced. The synergistic effect of optimizing the multiple parameters had a major influence. In further researches, it is necessary to find optimal design of the sink under impulsive and blast loads on the main construction. A numerical technique for development of reduced finite-element models of periodic and stochastic parametric oscillations of shells with shape imperfections was created. An algorithm for computer modeling of real geometric imperfections using spline curves and models of imperfections in the form of static buckling modes and natural oscillations modes, the amplitudes of which acquired different values in proportion to the thickness of the shell, was applied. A reduced model of parametric oscillations of a cylindrical shell with real and imperfections is constructed. The influence of the amplitude of the imperfection and the constant component of the load on the stiffness and geometric stiffness matrices of the shell was estimated. Product Description popup.authors Vorona Yurii Kryvenko Olga Lukianchenko Olga Pyskunov Sergii Pogorelova Olga Postnikova Tetiana popup.nrat_date 2024-01-26 Close