10. Soil-structure interaction#

◊ ISS = “OUI”,

Activation of the consideration of soil-structure interaction. In the case of soil-structure interaction, the seismic calculation will use parameters calculated using MISS3D (via CALC_MISS).

10.1. Soil calculation inputs/outputs#

10.1.1. Keyword CALC_IMPE_FORC#

◊ CALC_IMPE_FORC =/”OUI”, [DEFAUT]

/” NON “,

By default, the CALC_MISS operator is called the first time using the FICHIER option, which allows you to start an execution of MISS3D and retrieve the results in files, defined on a logical unit.

The user can deactivate this step by imposing CALC_IMPE_MISS =” NON “.In this case, you must define the logical units that correspond to existing files.

10.1.2. Tags UNITE_RESU_IMPE, UNITE_RESU_FORC#

♦ UNITE_RESU_FORC = uresfor [I]

◊ UNITE_RESU_FORC = uresfor [I]

These keywords make it possible to define the logical units associated with the impedances and equivalent seismic forces calculated by MISS3D.

In the case CALC_IMPE_FORC == “NON”, these keywords are mandatory and correspond to existing files that were generated previously.

In the case CALC_IMPE_FORC == “OUI”, these keywords are optional and make it possible to recover the impedances and equivalent seismic forces calculated by MISS3D.

10.1.3. Tags TABLE_SOL/MATER_SOL#

♦/TABLE_SOL = table [table]

/MATER_SOL = matsol

These keywords define the soil stratification used in calculation MISS3D.

One of these keywords must be defined if CALC_IMPE_FORC == “OUI”.

We can refer to the document [U7.03.12] for more details concerning these keywords.

10.2. Soil-structure interface#

10.2.1. Keyword VERSION_MISS#

♦ VERSION_MISS =/”V6.7”, [DEFAUT]

“V6.6”,

“V6.5”,

MISS3D version number. The value by default corresponds to the operating version of MISS3D.

MISS3D calculations on big models (or with a lot of frequencies) can be time consuming and memory intensive. Fortunately, these can be accelerated by activating one or two levels of parallelism. For more information you can consult the documentation [U2.06.07] and [U2.08.06].

10.2.2. Keywords GROUP_MA_INTERF, GROUP_NO_INTERF#

♦ GROUP_MA_INTERF = grma, [grma]

♦ GROUP_NO_INTERF = grno, [grno]

GROUP_MA_INTERF corresponds to the group of elements constituting the soil-structure interface.

GROUP_NO_INTERFcorrespond to the group of nodes where the coupling conditions are imposed. The aim is to automatically integrate the degrees of freedom of the nodes concerned to calculate the natural modes of the structure. The user should not add boundary conditions on this group as in the case of CALC_MISS.

In the case of a rigid foundation, the user must define a LIAISON_SOLIDE using the CHARGE keyword and a GROUP_NO_INTERF containing a node corresponding to the center of the foundation. In the case of a flexible foundation, no condition should be set on the GROUP_NO_INTERF which must contain all the nodes in the foundation.

10.2.3. Keywords TYPE_MODE/NB_MODE_INTERF#

TYPE_MODE = /” CRAIG_BAMPTON “, [DEFAUT]

/” INTERF “,

/”PSEUDO”,

Allows you to define the method for calculating the interface modes associated with GROUP_MA_INTERF.

If TYPE_MODE == “CRAIG_BAMPTON”, all link modes or constrained modes associated with the soil-structure interface are calculated.

If TYPE_MODE == “INTERF”, the user must specify the number of static modes to be calculated using the NB_MODE_INTERF keyword.

If TYPE_MODE == “PSEUDO”, six rigid body modes are calculated.

10.3. Soil calculation parameters#

◊ PARAMETRE = _F (

This keyword factor allows you to enter calculation parameters MISS3D. Please refer to document [U7.03.12] for more details.

10.4. Operands ACCE_X, ACCE_Y, ACCE_Z, DEPL_X,, DEPL_Y, DEPL_Z#

In the case of a transient calculation, these operands make it possible to provide the accelerograms using accelerations in one or more directions (ACCE_X, ACCE_Y, ACCE_Z) or movements imposed in one or more directions (DEPL_X, DEPL_Y, DEPL_Z).