Generalized Spring and Damper Property
Description: Defines the nominal property values for a generalized spring and damper structural element.
Format:
Example:
| Field | Definition | Type | Default |
|---|---|---|---|
| PID | Property identification number. | Integer > 0 | Required |
| K | Symbol indicating that the next 1 to 6 fields are stiffness values. | Character | Required |
| Ki | Nominal stiffness values in directions 1 through 6. See Remark 2 and 3. | Real | 0.0 |
| B | Symbol indicating that the next 1 to 6 fields are force per unit velocity damping. | Character | |
| Bi | Nominal damping coefficient in units of force per unit velocity. See Remark 3. | Real | 0.0 |
| GE | Symbol indicating that the next field is the structural damping constant. | Character | |
| GE1 | Nominal structural element damping coefficient. | Real | 0.0 |
| RCV | Symbol indicating that the next 1 to 4 fields are stress coefficients. | Character | |
| SA | Stress recovery coefficient in the translational component direction 1 through 3. | Real | 1.0 |
| ST | Stress recovery coefficient in the rotational component direction 4 through 6. | Real | 1.0 |
| EA | Strain recovery coefficient in the translational component direction 1 through 3. | Real | 1.0 |
| ET | Strain recovery coefficient in the rotational component direction 4 through 6. | Real | 1.0 |
Remarks:
- Ki, Bi, or GE1 may be made frequency dependent for modal frequency response analysis and K may be made force dependent for nonlinear analysis by use of the PBUSHT entry.
- For modal frequency response the normal modes are computed using the nominal Ki values. The frequency dependent values are used at every excitation frequency.
- If PARAM, W4 is not specified, GE1 is ignored in transient response analysis. (See Section 5, Parameters, for more information on W4.)
- The element stresses are computed by multiplying the stress coefficients with the recovered element forces.
- The element strains are computed by multiplying the strain coefficients with the recovered element displacements.
- The K, B, GE or RCV options may be specified in any order.