1131x
003586
2024-01-29

Line Releases

A line release allows the model to be decoupled along a line. You can use it to model, for example, two surfaces being loosely connected or transferring only compressive forces at the common boundary line. The degrees of freedom along the line are controlled by the 'Line Release Type' that describes the properties of the hinge.

Info

Line releases result in double nodes belonging to different parts of the model.

Line Release Type

The properties of the release are described by a hinge, which in principle corresponds to a line hinge. Select the release type in the list or define a new type with the New button. The corresponding dialog box is described in the Line Release Types chapter.

Released Objects

Specify the numbers of the members, surfaces, and solids that are decoupled along the line. You can use the Select Individually button to graphically define the objects in the work window.

Release Generation

RFEM generates a copy of the line at the same location where the released deformations are allowed. In the list, select whether to place the release (hinge) on the 'Original line' or the 'Released line'. The setting specifies with which part of the model the hinge is deforming, thus having an effect on the results: For large deformation analyses or postcritical analyses, different coordinate systems for the original as well as the released line are often the result in the course of the deformation.

When you have defined a line, the number of the generated line including the node numbers is shown. In the navigator, it is marked with the added 'Line Release' labeling. It cannot be edited.

Definition Objects

The released line is automatically created as a copy with the corresponding nodes. However, if you want to use one or more existing nodes for the generated line, you can specify the corresponding numbers in this dialog section. This affects the results because the displacements at these nodes are not released.

Tip

This webinar demonstrates how to manually define the definition nodes for a girder grillage model with multiple surfaces in order to decouple the system.

Options

With the 'Deactivate release' check box, you can cancel the decoupling along the line for certain analyses without deleting the line release.

Parent section