2. Operands

2.1. Operand RESULTAT

♦ RESULTAT = RESULTAT

Field name evol_elasou evol_noli from the basic calculation (on the geometry for which we want to calculate the reinforcement).

2.2. Operand INST

♦ INST = inst

Real specifying the moment at which the return takes place.

2.3. Operands BETON and ACIER

♦ BETON = BETON

Data structure of the mater_sdaster type defining the elastic properties of the concrete material (Young’s Modulus, \(E\), and Poisson’s Ratio, \(\nu\)), as defined by DEFI_MATERIAU/ELAS.

♦ ACIER = ACIER

Data structure of the mater_sdaster type defining the characteristics of the steel material (Young’s Modulus, \(E\), and Poisson’s Ratio, \(\nu\)), as defined by DEFI_MATERIAU/ELAS.

2.4. Operand GROUP_MA_EXT

♦ GROUP_MA_EXT =/gr_ma_ext

Name of the seg2 group of elements defining the outer contour of the geometry. The connectivity of these groups must define closed geometries.

2.5. Operand GROUP_MA_EXT

◊ GROUP_MA_INT =/gr_ma_int

List of seg2 mesh groups defining the internal contours of geometry. The connectivity of these groups must define closed geometries.

2.6. Operand SCHEMA

♦ SCHEMA = /' SECTION ',

/' TOPO ',

One of the two possible optimization schemes must be selected by the user. In the absence of the operand, the optimization scheme “SECTION” will be chosen by default.

2.7. Operands SIGMA_C and SIGMA_Y

♦ SIGMA_C = fc,

♦ SIGMA_Y = fy,

Resistance limit values considered in the optimization. SIGMA_C represents the compressive strength of concrete and SIGMA_Y represents the tensile strength of steel.

2.8. Operands PAS_X and PAS_Y

◊ PAS_X = not_x,

◊ PAS_Y = not_y,

The user can define the mesh step used for the interpolation of values in the constraint fields. Two values are required: one value for the step in the X direction and one for the step in the Y direction.

2.9. Operand TOLE_BASE

◊ TOLE_BASE =/0.1,

/tole_1,

The tolerance value TOLE_BASE makes it possible to define the fusion distance between the stress peaks during the interpolation of the stress field, on the basic model, i.e. on the input result of the macro (geometry for which we want to calculate the reinforcements). The value provided represents a percentage of the longest distance in x, y, or z between base mesh nodes.

2.10. Operand TOLE_BT

◊ TOLE_BT =/0.1,

/tole_2,


The tolerance value TOLE_BT allows you to define the fusion distance between two or more nodes in the mesh model. The value provided represents a percentage of the longest distance in x, y, or z between base mesh nodes.

2.11. Operand MAX_ITER

◊ NMAX_ITER =/150,

/maxiter,

This keyword allows the user to define the maximum number of iterations performed by the chosen optimization scheme.

2.12. Operands RESI_RELA_TOPO and RESI_RELA_SECTION

◊ RESI_RELA_SECTION =/1E-6,

/conv_1,


◊ RESI_RELA_TOPO =/1E-5,

/conv_2,


The convergence precision of the optimization procedure can be defined by the user. The convergence value RESI_RELA_SECTION controls the stopping of the optimization procedure, whether of type SECTION or TOPO. The value RESI_RELA_TOPO triggers the topology optimization procedure and is only used for the TOPO schema.


For an optimization performed exclusively with the option SCHEMA = 'SECTION', the parameter RESI_RELA_TOPO is ignored.

2.13. Operand CRIT_SECTION

◊ CRIT_SECTION =/0.5,

/sevol


The CRIT_SECTION operand allows you to define the maximum evolution of the sections of the elements during the optimization algorithm. A value of 0.5, equivalent to a maximum allowable change of ± 50%, is imposed by default.

2.14. Operand SECTION_MINI

♦ SECTION_MINI = /minsec,


The SECTION_MINI operand allows the user to define the minimum cross section for elements whose axial force tends to zero. This parameter is used for both schema SECTION and TOPO.

2.15. Operand CRIT_ELIM

◊ CRIT_ELIM =/0.1,

/melim,


The CRIT_ELIM operand allows you to define the maximum rate of elimination of elements. This value represents a percentage of all items in the initial system. This parameter is only used for schema TOPO and is ignored if schema SECTION is chosen.

2.16. Operand LONGUEUR_MAX

♦ LONGUEUR_MAX = maxlon,


The value LONGUEUR_MAX limits the generation of elements in the BT model. The elements, connecting rods or tie rods, have the maximum length of the given value.

2.17. Operand INIT_ALEA

◊ INIT_ALEA = seed,

The INIT_ALEA keyword initializes the seed of random sequences used for a random draw. If this operand is entered, two reinforcement calculations with the same initialization then produce the same result.

2.18. Keyword factor DDL_IMPO

♦ | DX = DX, | DY = dy, )

This keyword factor makes it possible to apply imposed movements on a group of nodes. It is the responsibility of the user to fill in the same boundary conditions used for the calculation on the initial geometry (basic calculation). The syntax is the same as for the AFFE_CHAR_MECA operator [U4.44.01].

2.18.1. Operand GROUP_NO

♦ GROUP_NO = gr_no

Node group associated with boundary conditions.

2.18.2. DX and DY operands

♦ | DX = DX,

| DY = dy,

Values of the imposed nodal movements defined in the global coordinate system for defining the mesh.

2.19. Keyword factor FORCE_NODALE

♦ | FX = fx, | FY = fy, )

Keyword factor that can be used to apply nodal forces, defined component by component in the global coordinate system, to groups of nodes. It is the responsibility of the user to fill in the same boundary conditions used for the calculation on the initial geometry (basic calculation). The syntax is the same as for the AFFE_CHAR_MECA operator [U4.44.01].

2.19.1. Operand GROUP_NO

♦ GROUP_NO = gr_no

Group of nodes associated with nodal load conditions.

2.19.2. FX and FY operands

♦ | FX = fx,

| FY = fy,

Values of the imposed nodal forces defined in the global coordinate system for defining the mesh.