Polidor BRATU


For a linear dynamic system (m, c, k) with several degrees of freedom qi, i = , amortization may be assessed only based on the modal amortization ratio    corresponding to the vibration modulus r, in the direction of the qr degree of freedom for i = r . If a dynamic structure consists of several systems j = 1, 2, 3,..,s with linear viscoelastic connections between them, that is the dynamic systems are physically coupled by the three parametric quantities m, c, k, there must be assessed the equivalent amortization or the compound amortization  depending on the physical structure of the coupled systems. The research conducted for this purpose highlighted the possibility of establishing an analytical relationship meant to ensure the calculation of the modal amortization ratio for a dynamic structure composed of several systems coupled among them. This article presents the equivalent modal amortization ratio for the linear parallelly coupled viscoelastic systems.

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