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Since material damping sums with that specified in load cases, this procedure reduces stiffness-proportional damping only in affected elements, without affecting the rest of the model. Nonlinear material behavior will then serve to dissipate energy dissipation.
When damping reduction disrupts convergence, users should apply Hilber-Hughes-Taylor integration to the load case using a small negative HHT-alpha value. The prescriptive range is 0 to -1/3. A value of -1/24 should improve the rate of convergence, cutting analysis duration by as much as a factor of three.
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