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Calculate static modes for an imposed unit displacement, force, or acceleration. Coupling modes (interface modes) can also be calculated to define a smaller generalized model.

A static mode is the static deformation of an isostatic or hyperstatic structure upon which:

in a**blocked degree of freedom * (node - component) a unitary imposed displacement,

in a**degree of free liberty* (node - component) a unitary nodal force,

in a**direction*, a unit imposed acceleration,

in a**degree of liberty* (node - component) a unit imposed acceleration.

The coupling modes correspond to the modes of the substructure condensed statically on the interface. These modes, defined only on the interface, are then recorded statically over the entire substructure.

The operator makes it possible to calculate all the static modes corresponding to several node-component pairs. The stiffness matrix should be assembled using a set of kinematic boundary conditions sufficient for all solid body modes to be removed (operators AFFE_CHAR_MECA [U4.44.01] or AFFE_CHAR_CINE [U4.44.03]). It is possible to request only a portion of the static modes corresponding to these kinematic conditions.

The product concept can be used to complete a modal base of natural vibration modes (operator DEFI_BASE_MODALE [U4.64.02] or DYNA_ALEA_MODAL [U4.53.22]), to determine the loads required to calculate the driving movement under seismic excitation (operator CALC_CHAR_SEISME [U4.63.01]) and to introduce movements to multi-support anchors or correction modes in spectral analysis (operator COMB_SISM_MODAL [U4.84.01]).

Produces a mode_meca concept.

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