Search academic texts

Information × Registration Number 0221U103032, 0119U002578 , R & D reports Title Numerical methods for the analysis and prediction of nonlinear vibrations, dynamic stability as well as crisis and chaotic behavior of elastic systems popup.stage_title Head Ivanchenko Grygorii M., Доктор технічних наук Registration Date 12-02-2021 Organization Kyiv National University of Construction and Architecture popup.description2  The issues of predicting and forecasting critical states and crises in a strongly nonlinear non-smooth discontinuous vibro-impact system are considered. The description of the vibro-impact platform model, which is used in the construction industry for compaction and formation of large concrete products, is carried out. A technique for studying the platform model when changing the three leading parameters has been developed. The analysis of the dependences of the vibration amplitudes and the Lyapunov exponent on the values of the leading parameters provided an opportunity to determine the dangerous zones of the parameters that can lead the system to a critical or undesirable state. Methods and tools for predicting and diagnosing chaotic states of the vibro-impact system have been developed. An approach is presented that allows to improve the existing computer diagnostic models of multi-storey frame buildings for the analysis of their seismic responses by taking into account the seismic horizontal movement of the ground and wavelet analysis methods. The wavelet analysis of seismic influence and reactions of a frame structure is carried out, which allowed to qualitatively investigate localization of maximum values in frequency-time space and to give recommendations on application of the mode superposition method. It is shown that the consideration of transverse bending waves in columns significantly affects the bending moments at the points of attachment of columns to the foundation and causes uneven deformation of the whole building. It is revealed that taking into account the wave reactions in the columns, the normal modes of oscillations of the model change significantly. Product Description popup.authors Bazhenov Viktor A Vabishchevych Maksym O Vorona Yurii V Zhuk Yaroslav O Lukianchenko Olga O Maksymiuk Yurii V Pogorelova Olga S Postnikova Tetiana G popup.nrat_date 2021-02-12 Close