REINF263 Element Description

For a structural reinforcing analysis, use REINF263 with standard 2D solid and shell base elements to provide extra reinforcing to those elements. For a thermal reinforcing analysis, the supported base elements are thermal planes PLANE292 and PLANE293.

The element uses a smeared approach and is suitable for modeling evenly spaced reinforcing fibers that appear in layered form. Each reinforcing layer contains a cluster of fibers with unique orientation, material, and cross-section area, and is simplified as a homogeneous membrane having unidirectional stiffness. You can specify multiple layers of reinforcing in one REINF263 element. The nodal locations, degrees of freedom, and connectivity of the REINF263 element are identical to those of the base element.

REINF263 has plasticity, stress-stiffening, creep, large-deflection, and large-strain capabilities.

For more information, see Reinforcing and Direct Element Embedding in the Structural Analysis Guide.

Figure 263.1: REINF263 Geometry

Figure 263.2: REINF263 Coordinate System

Uniaxial Stress State	Plane Stress State

X0 = Layer x axis if layer system LSYS and layer-orientation angle θ are not specified (default).

Xc = Layer x axis if a local coordinate system for the layer is specified (SECDATA,,,KCN)

Xf = Layer x axis if layer orientation angle θ is specified (SECDATA,,,,THETA)

REINF263 Input Data

The geometry and nodal locations for this element are shown in Figure 263.1: REINF263 Geometry. The REINF263 element and its base element share the same nodes and element connectivity.

You can easily create REINF263 elements from the selected base elements via the EREINF command. Section commands (SECTYPE and SECDATA) define the material ID, cross-section area, spacing, location, and orientation of reinforcing fibers. See Reinforcing and Direct Element Embedding in the Structural Analysis Guide for more information about creating REINF263 elements.

Each reinforcing layer can contain a cluster of fibers with unique orientation, material, and cross-section area, simplified as a homogeneous membrane having unidirectional stiffness.

The equivalent thickness h of the smeared reinforcing layer is given by:

where A is the cross-section area of a single fiber, and S is the distance between two adjacent fibers.

REINF263 can also be used to model homogeneous reinforcing membranes. The spacing input S is ignored and always set to 1.0 for reinforcing membranes. Therefore, the thickness h is equal to the cross-section area input A.

For a structural analysis, REINF263 supports a plane-stress or uniaxial-stress state (SECCONTROL,,,MEMOPT). For a thermal analysis, specify thermal conductivity KXX. Select the plane-stress state for homogeneous reinforcing membranes, and the uniaxial-stress state for clusters of reinforcing fibers.

The coordinate systems for one reinforcing layer are shown in Figure 263.2: REINF263 Coordinate System. Each reinforcing layer is indicated by its intersection points (II, JJ for linear base elements, and II, JJ, KK, for quadratic base elements) with the base elements. Fibers in this layer are always parallel to the first coordinate axis x. The x axis is default to the first parametric direction S1 at the center of the layer. The default axis is defined as

where

You can reorient the default layer coordinate system by projecting a local coordinate system (LOCAL) to the layer plane. One local coordinate system is allowed for each layer. The local coordinate system reference number is given via the SECDATA command.

You can further reorient the layer coordinate system by angle θ (in degrees) for each layer. The value of θ is also specified for each layer via the SECDATA command. For more information about visualizing fiber orientations, see /PSYMB.

You can use REINF263 to reinforce 2D solid elements with plane-stress, plane-strain, axisymmetric (with or without torsion), and generalized plane-strain behaviors. The element can also reinforce axisymmetric shells or membranes (with or without uniform torsion). The element accounts for various base element behaviors automatically.

REINF263 enables you to specify tension-only or compression-only reinforcing fiber behavior (SECCONTROL,TENSKEY). This option is not available when the plane-stress state is selected (SECCONTROL,,,MEMOPT).

REINF263 allows tension-only or compression-only reinforcing fibers. You can specify the desired fiber behavior (SECCONTROL).

The element can account for redundant base element material where the reinforcing fibers are located (SECCONTROL,,REMBASE).

For a structural analysis, REINF263 allows body-force-density element loading (BFE), as shown in these examples:

If applying body-force density to REINF263 elements, the program applies a uniform load to all members in the element. You can apply non-uniform body-force density to individual members via the mesh-independent method by loading to MESH200 elements.

Apply other structural element loading only to the base element. The temperature of the REINF263 element is identical to the temperature of the base element in a structural analysis.

For thermal reinforcing analysis, REINF263 allows heat-generation (HGEN) element loading (BFE), as shown in these examples:

You can apply an initial state to this element in either of the following ways:

For cases involving many elements, an easier and more efficient method is available. Using the mesh-independent method, you can apply an initial state to the MESH200 elements first. Mechanical APDL then transfers the initial state to the newly created reinforcing elements automatically.

A summary of the element input follows.

REINF263 Output Data

The solution output associated with the element is in two forms:

The following figure illustrates the axial stress component:

Figure 263.3: REINF263 Stress Output

Uni-axial Stress State	Plane Stress State

x = x0, x1, or xf is the layer x axis.

Unlike layered solid or shell elements (such as SHELL181), REINF263 always outputs the element solution for all reinforcing layers. You can select solution items for a specific reinforcing layer (LAYER) for listing and visualization by using full graphics (/GRAPHICS,FULL). Visualization via PowerGraphics (/GRAPHICS,POWER) is not affected by the LAYER command; all reinforcing layers are displayed simultaneously. See the Basic Analysis Guide for ways to review results.

REINF263 element solution is always output in the layer coordinate system and does not support transformation to a different coordinate system. RSYS has no effect on REINF263 element solution.

To inspect REINF263 element results, select only REINF263 element results or adjust translucency level of the base elements before executing any plotting command. REINF263 display options are also available directly via the GUI (Main Menu> Preprocessor> Sections> Reinforcing> Display Options).

The Element Output Definitions table uses the following notation:

A colon (:) in the Name column indicates that the item can be accessed by the Component Name method (ETABLE, ESOL). The O column indicates the availability of the items in the file jobname.out. The R column indicates the availability of the items in the results file.

In either the O or R columns, “Y” indicates that the item is always available, a letter or number refers to a table footnote that describes when the item is conditionally available, and “-” indicates that the item is not available.

Table 263.3: REINF263 Item and Sequence Numbers lists output available via ETABLE using the Sequence Number method. See Creating an Element Table and The Item and Sequence Number Table in this document for more information. The following notation is used in Table 263.3: REINF263 Item and Sequence Numbers:

The i value (where i = 1, 2, 3, ..., NL) represents the reinforcing member number of the element. NL is the maximum reinforcing member number (1 NL 250).

REINF263 Assumptions and Restrictions

REINF263 Product Restrictions

There are no product-specific restrictions for this element.