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*LMASS

Data format:

An arbitrary number of lines comprising 3 values each

IM JDIR AMASS

Status :

Optional (dynamics or modal analysis)

Purpose :

To define lumped masses and inertia

Details :

Parameter	Description
IM	Identification number of the node
JDIR	Index of the affected degree of freedom (1,2,3 for translations and 4,5,6 for rotations)
AMASS	Value of the mass or inertia at node IM

Notes : This keyword refers to masses and not forces. The values specified here are added to the diagonal terms of the mass matrix . If the user wishes to model the effect of some equipment hanging on a cable , for instance, he must give its weight under keyword PLOAD and its inertia under keyword LMASS.

Example :

*LMASS

17 1 4852.0
17 2 8027.04
17 3 10558.68
18 1 11090.32
18 2 18347.51
18 3 24134.13