|
*Damping |
 
|
*Damping
|
*Damping |
|
To incorporate damping into a dynamic analysis.
Refer to Damping for further information on this feature.
A block of lines which define the damping parameters as a function of element set. The block of lines can be repeated as often as necessary.
Block defining damping coefficients for standard type.
TYPE=STANDARD
SET=Set Name
Stiffness Coefficient, Mass Coefficient
Block defining individual stiffness damping coefficients for each mode of deformation, namely axial, bending and torsion.
TYPE=DEFORMATION
SET=Set Name
Axial Coefficient, Bending Coefficient EIyy, Torsional Coefficient, Mass Coefficient [, Bending Coefficient EIzz]
The specification of damping for an element set using the *DAMPING keyword precludes the specification of damping for the same element set using the *DAMPING RATIO keyword, and vice versa. Deformation mode damping (TYPE=DEFORMATION) pertains specifically to time domain analysis, and should be omitted for frequency domain analysis. Bending Coefficient EIzz defaults to Bending Coefficient, which means that the same damping is applied to bending about the local y and local z axes.
To specify damping coefficients.
Input: |
Description |
Element Set Name: |
The name of the element set to which the damping coefficients are assigned. This defaults to all elements. |
Stiffness Coefficient: |
The stiffness-proportional damping coefficient. This defaults to zero. |
Mass Coefficient: |
The mass-proportional damping coefficient. This defaults to zero. |
(a)Structural damping is generally specified directly in terms of stiffness and mass proportional damping coefficients. Refer to Damping Coefficients for further details.
(b)If damping coefficients are assigned to an element set in this table, the same element set may not be referenced in the Damping – Deformation or Damping Ratio tables.
To specify deformation mode damping in a time domain dynamic analysis.
Input: |
Description |
Element Set: |
The name of the element set to which the damping data is assigned. This defaults to all elements. |
Axial Coefficient: |
The axial stiffness-proportional damping coefficient. This defaults to zero. |
Bending Coefficient (EIyy): |
The bending stiffness-proportional damping coefficient for bending about the element local-y axis. This defaults to zero. |
Bending Coefficient (EIzz): |
The bending stiffness-proportional damping coefficient for bending about the element local-z axis. This defaults to the coefficient specified for the local-y axis. |
Torsion Coefficient |
The torsional stiffness-proportional damping coefficient. This defaults to zero. |
Mass Coefficient |
The mass-proportional damping coefficient. This defaults to zero. |
(a)Specification of deformation mode damping allows you to define individual stiffness damping coefficients for each of the structure deformation modes, namely, axial, bending and torsion. Refer to Deformation Mode Damping for further details.
(b)If damping is assigned to an element set in this table, the same element set may not be referenced in the Damping or Damping Ratio tables.
(c)This table is not relevant for frequency domain dynamic analysis.