This section describes how to create a continuum shell composite
layup.
Abaqus
models a continuum shell composite layup using continuum shell elements that
fully discretize each ply but have a kinematic behavior that is based on shell
theory. Continuum shell composite layups are composed of plies made of
different materials in different orientations. A layup can contain a different
number of plies in different regions. For more information, see
Composite layups.
Continuum shell composite layups are expected to have a single element
through their thickness, and that single element contains multiple plies that
are defined in the ply table. If the region to which you assign your continuum
shell composite layup contains multiple elements, each element will contain the
plies defined in the ply table, and the analysis results will not be as
expected.
You choose the stacking direction of the continuum shell elements in the
layup, which allows
Abaqus
to model the through-thickness response more accurately. In addition, continuum
shell composite layups take into account double-sided contact and thickness
changes, which provides more accurate contact modeling than conventional shell
composite layups. For more information, see
Shell section behavior.
When you create continuum shell composite layups, you must choose a
section integration method. You can choose to provide the section property data
before the analysis (a pre-integrated continuum shell composite layup) or to
have
Abaqus
calculate (integrate) the cross-sectional behavior from integration points
during the analysis.
Continuum shell composite layups integrated during the analysis allow the
cross-sectional behavior to be calculated by numerical integration through the
continuum shell thickness, thus providing complete generality in material
modeling. Any number of material points can be defined through the thickness,
and the material response can vary from point to point. You generally use
continuum shell elements integrated during analysis when the composite layup
includes nonlinear material behavior. You must use continuum shell elements
integrated during analysis to model heat transfer. For more information, see
Using a shell section integrated during the analysis to define the section behavior.
Linear moment-bending and force-membrane strain relationships can be
defined using pre-integrated continuum shell composite layups. In this case all
calculations are done in terms of section forces and moments. The section
properties are specified by an elastic material; optionally, you can also apply
an idealization based on assumptions about the expected behavior or makeup of
the layup. You should use pre-integrated continuum shell composite layups if
the response of the layup is linear elastic, and its behavior is not dependent
on changes in temperature or predefined field variables. For more information,
see
Using a general shell section to define the section behavior.
After you have created a continuum shell composite layup, you can use a
ply stack plot to view a graphical representation of a core sample through a
region of the layup. For more information, see
Viewing a ply stack plot.