Taking into account the difference in the support excitation for multi-supported structures

DOI: 10.37153/2618-9283-2021-6-21-28

Authors:  
Rubric:     Theoretical and experimental studies   
Key words: multi-support structures, non-synchronicity of oscillations, correlation function, coherence index, amplitude divergence index inhomogeneity of the acceleration field
Annotation:

Three characteristics are proposed to describe the excitation differences under supports for calculating multi-supported structures. These characteristics include the non-synchronicity indicator t0, the incoherence indicator r and the non-uniformly scaled indicator z. The first characteristic shows the time shift between the excitations, the second characteristic shows the difference in the excitation frequency composition, and the third one shows the difference in the action amplitudes. To estimate the nonsynchrony index, two approaches have been proposed – maximizing the correlation function and minimizing the norm of the excitation difference. The proposed parameters fully characterize the acceleration inhomogeneity field at the construction site. However, they affect the system response in different ways. Small deviations in the index of excitation amplitudes z weakly reduce the structure response. As for the excitation incoherence, this effect can bring the system closer or away from resonance.

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