5.5. Reinforcing Elements

Reinforced materials are used extensively in civil engineering construction and composite structures. Use reinforcing elements to model reinforcement in either of two forms: cable (such as steel rebar in reinforced concrete) or fiber (such as the carbon fiber in fiber-reinforced composites).

Two methods are supported for modeling reinforcing cables or fibers:

For further information, see the documentation for the reinforcing elements (REINFnnn).

5.5.1. Discrete Reinforcing

The discrete reinforcing method allows reinforcing fibers to be accounted for individually. This method is suitable for modeling sparsely placed fibers, or fibers with nonuniform properties, such as cross-section area, material, spacing, and orientation.

The discrete reinforcing element REINF264 is used to add individual fibers to 3-D link, beam, shell and solid elements. Multiple reinforcing fibers are allowed in a single element.

5.5.2. Smeared Reinforcing

The smeared reinforcing method is suitable for modeling clusters of reinforcing fibers appearing in layer or sheet form. Each layer of fibers is simplified as a homogeneous membrane having unidirectional stiffness.

Fibers in the same layer must have uniform cross-section, material, spacing, and orientation.

The smeared reinforcing elements are:

REINF263 -- Used with 2-D solids such as plane stress, plane strain, axisymmetric and generalized plane strain, and axisymmetric shell elements.
REINF265 -- Used with 3-D solid and shell elements.