This option is used to specify a shell cross-section.
Products: ABAQUS/Standard ABAQUS/Explicit
Type: Model data
Level: Part Part Instance
Set this parameter equal to the name of the element set containing the shell elements for which the section behavior is being defined.
Include this parameter if the shell is made up of several layers of material.
Set this parameter equal to the name of the material of which the shell is made.
In an ABAQUS/Explicit analysis, set this parameter equal to the name of a section controls definition (see “Section controls,” Section 13.1.4 of the ABAQUS Analysis User's Manual) to be used to specify the second-order accurate element formulation option, a nondefault hourglass control formulation option, or scale factors.
In an ABAQUS/Standard analysis, set this parameter equal to the name of a section controls definition to be used to specify the enhanced hourglass control formulation (see “Section controls,” Section 13.1.4 of the ABAQUS Analysis User's Manual) or to be used in a subsequent ABAQUS/Explicit import analysis.
Set this parameter equal to a mass per unit surface area of the shell.
If this parameter is used, the mass of the shell includes a contribution from this parameter in addition to any contribution from the material definition.
Include this parameter to indicate that the shell thickness should not be read from the data lines but should be interpolated from the thickness specified at the nodes with the *NODAL THICKNESS option. For composite sections the total thickness is interpolated from the nodes and the thicknesses of the layers specified on the data lines are scaled proportionally. This parameter is ignored for continuum shells.
Include this parameter to define the distance (as a fraction of the shell thickness) from the shell midsurface to the reference surface (containing the nodes of the element). This parameter accepts positive or negative values or the labels SPOS or SNEG.
Positive values of the offset are in the positive normal direction (see “Shell elements: overview,” Section 15.6.1 of the ABAQUS Analysis User's Manual). When OFFSET=0.5 (or SPOS), the top surface of the shell is the reference surface. When OFFSET=–0.5 (or SNEG), the bottom surface of the shell is the reference surface. The default is OFFSET=0, which indicates that the middle surface of the shell is the reference surface. This parameter is ignored for continuum shells.
Set this parameter equal to the name of an orientation definition (“Orientations,” Section 2.2.5 of the ABAQUS Analysis User's Manual) to be used with material calculations in this definition of shell section behavior. This orientation will be used for material calculations and stress output in the individual layers, for the section forces output, and for the transverse shear stiffness.
It is possible to use a different orientation definition for material calculations in the individual layers of a composite shell by referencing an orientation definition or giving an orientation angle (in degrees, positive counterclockwise relative to the shell local directions) on each layer definition data line. Any layer definition line that does not have an orientation reference or an angle specified will use the orientation defined here.
Include this parameter to define the shell thickness direction behavior.
Set this parameter equal to a nonzero value to cause the thickness direction strain under plane stress conditions to be a linear function of the membrane strains. The value of the POISSON parameter must be between –1.0 and 0.5.
Set POISSON=ELASTIC to automatically select this parameter value based on the initial elastic part of the material definition.
Set POISSON=MATERIAL in an ABAQUS/Explicit analysis to cause the thickness direction strain under plane stress conditions to be a function of the membrane strains and the in-plane material properties.
In ABAQUS/Standard the default is POISSON=0.5; in ABAQUS/Explicit the default is POISSON=MATERIAL.
This parameter is relevant only for continuum shells.
This parameter defines the continuum shell stack or thickness direction. Set this parameter equal to 1, 2, 3, or ORIENTATION. The default is STACK DIRECTION=3. The ORIENTATION parameter must also be used if STACK DIRECTION=ORIENTATION.
Set SECTION INTEGRATION=SIMPSON (default) to use Simpson's rule for the shell section integration.
Set SECTION INTEGRATION=GAUSS to use Gauss quadrature for the shell section integration. Gauss quadrature cannot be used for heat transfer or thermally coupled shell elements.
Use this parameter to select the mode of temperature and field variable input used on the *FIELD, the *INITIAL CONDITIONS, or the *TEMPERATURE options.
Omit the TEMPERATURE parameter to define the predefined field by its magnitude on the reference surface of the shell and its gradient through the thickness.
Set TEMPERATURE=n, where n is the number of predefined field variable points in the shell or in each layer if the COMPOSITE parameter is used, to define the predefined field at n equally spaced points through each layer of the shell section.
In a heat transfer analysis step or a coupled temperature-displacement analysis step when the *FIELD option is used to specify values of predefined field variables, the TEMPERATURE parameter is required to specify the number of field variable points in the shell. The number of temperature points in the shell with temperature degrees of freedom is defined by the number of integration points specified on the data lines.
This parameter is relevant only for continuum shells.
Set this parameter equal to an effective thickness modulus. The default effective thickness modulus is twice the initial in-plane shear modulus based on the material definition.
First (and only) line:
Shell thickness. This value is ignored if the NODAL THICKNESS parameter is included.
Number of integration points to be used through the shell section. The default is five points if Simpson's rule is used and three points if Gauss quadrature is used. The number of integration points must be an odd number for Simpson's rule and, in an ABAQUS/Standard analysis, is equal to the number of temperature degrees of freedom at a node of the element if this section is associated with heat transfer or coupled temperature-displacement elements. This number must be at least 2 and less than or equal to 7 for Gauss quadrature. For Simpson's rule it must be at least 3, except in a pure heat transfer analysis, where the number of integration points can be 1 for a constant temperature through the shell thickness.
First line:
Layer thickness. This value is modified if the NODAL THICKNESS parameter is included.
Number of integration points to be used through the layer. The default is three points if Simpson's rule is used and two points if Gauss quadrature is used. The number of integration points must be an odd number for Simpson's rule and, in an ABAQUS/Standard analysis, determines the number of temperature degrees of freedom at a node of the element if this section is associated with heat transfer or coupled temperature-displacement elements. This number must be less than or equal to 7 for Gauss quadrature.
Name of the material forming this layer.
Name of the orientation to be used with this layer or the orientation angle, 
, (in degrees) measured positive counterclockwise relative to the orientation definition given with the ORIENTATION parameter, where 
. If the ORIENTATION parameter is not included, is measured relative to the default shell local directions (see “Orientations,” Section 2.2.5 of the ABAQUS Analysis User's Manual).
Repeat this data line as often as necessary. Use one data line for each layer of the shell. The order of the laminated shell layers with respect to the positive direction of the shell normal is defined by the order of the data lines.