18. Keyword RIGI_MISS_3D

18.1. Syntax

RIGI_MISS_3D = _F (

♦ GROUP_MA_POI1 = l_gma, [l_group_ma]

◊ GROUP_MA_SEG2 = l_gma, [l_group_ma]

♦ FREQ_EXTR = freq, [real]

◊ UNITE_RESU_IMPE = unit (30), [integer (default)]

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18.2. Affordable characteristics

The use of this keyword is dedicated to foundation separation problems in order to better take into account the ground spring carpet than does RIGI_PARASOL, which distributes 6 global stiffness under a foundation in proportion to the areas of the elements surrounding its nodes.

This keyword will affect the exact terms of an impedance matrix calculated by MISS3Dpour all interface degrees of freedom (3 times the number of nodes) and for a given extraction frequency. The assignment of these terms (modeling “DIS_T”) is then done to the point cells POI1des nodes of the surface foundation and possibly to the lines of the network from SEG2superposé to the foundation to represent the transverse links between nodes.

18.3. Description of operands

♦ GROUP_MA_POI1

Group of point meshes of foundation nodes.

◊ GROUP_MA_SEG2

Group of SEG2 meshes transversely connecting the nodes of the foundation.

♦ FREQ_EXTR

Impedance matrix extraction frequency.

◊ UNITE_RESU_IMPE

Logical unit of the impedance matrix calculated by CALC_MISS option FICHIER.