PARAM, G

Bulk Data Entry Specifies the uniform structural damping coefficient for dynamic analyses.

Parameter Values Description
G <Real>

Default = 0.0

 To obtain the value for the parameter G, multiply the critical damping ratio, C / C 0 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4qaiaac+ cacaWGdbWaaSbaaSqaaiaaicdaaeqaaaaa@391F@ by 2.0.

Comments

  1. To achieve identical displacements in Modal frequency response or Modal transient analyses when the SDAMPING Bulk Data Entry is used instead of PARAM, G, the steps described here can be followed:
    • The TYPE field in the TABDMP1 or TABDMP2 Bulk Data Entry should be set to CRIT. This TABDMP1 Bulk Data Entry is referenced by the SDAMPING Subcase Information Entry.
    • Set the damping value (field g i MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4zamaaBa aaleaacaWGPbaabeaaaaa@37FC@ ) in the TABDMP1 Bulk Data Entry equal to half of the value of PARAM, G (that is set the constant value to C / C 0 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8srps0lbbf9q8WrFfeuY=Hhbbf9v8 qqaqFr0xc9pk0xbba9q8WqFfea0=yr0RYxir=Jbba9q8aq0=yq=He9 q8qqQ8frFve9Fve9Ff0dmeaacaGacmGadaWaaiqacaabaiaafaaake aacaWGdbGaai4laiaadoeadaWgaaWcbaGaaGimaaqabaaaaa@3C00@ ).
    • Set PARAM,KDAMP,-1.
  2. If GE is specified on MATx material data, the table ID for GE on MATTx material data or specified in the CELAS2, PELAS, PELAST, PBUSH, PBUSHT, PCOMP, PCOMPP, and PCOMPG data, then both GE and PARAM,G are used in analysis (they are added).
  3. PARAM,G will be applied to the whole stiffness matrix (including reduced stiffness in DMIG), if specified in residual run. If both PARAM,G and the reduced structural damping in DMIG are used in residual run, both will be applied in analysis.
  4. PARAM, G is ignored in Component Mode Synthesis (CMSMETH) superelement creation run.