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Résumé :
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Dynamic characteristics are analytically investigated for a single degree of freedom structure with a Maxwell element (SSME). Eigenvalues are obtained analytically and approximated by a perturbation method. Then, cases are sorted by a stiffness ratio λ : the ratio of a structural spring to an auxiliary spring. For a small λ , the optimal damping ϕc provides the maximum damping ratio. For a large λ , the lower and upper critical dampings ϕa and ϕb provide duplex eigenvalues. These values are approximated by simple terms. To reduce transient response, λ should be large, and ϕ should be around ϕc , ϕa , and ϕb , which provide the SSME with large damping. For a stationary excitation, the optimal damping ϕd is introduced to produce the minimum peak deformation. In fact, ϕd is larger than ϕc and ϕb , and provides larger stiffness and a smaller damping ratio. For a seismic excitation, some cases with ϕd might reduce deformation more than those with ϕc and ϕb , but must support larger stress in the Maxwell element. Thus, ϕ should be based on design constraints.
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