Abstract:

A modal superposition method for modal sensitivity analysis of viscoelastically damped structures is established based on a simplified form of modal analysis of viscoelastically damped structures, in which the modal sensitivity can be calculated using the modes obtained. Its form is simple and similar to the form of the modal superposition for modal sensitivity analysis of linear viscously damped structures, so the calculation is much simpler. The method proposed lays the foundation of dynamic design and structure modification of viscoelastically damped structures. An example of sensitivity analysis of the vibrating modes of a limited freedom discrete viscoelastically damped structure is given. The example demonstrates that the contribution of creeping modes to the sensitivity analysis of eigenvectors of vibrating modes is small and the calculation has a good accuracy when the sensitivity of eigenvectors of many vibrating modes is calculated.

Key words: viscoelast icity, modal analysis, sensitivity