2685x
000267
2024-02-08

Nodal Loads

Nodal loads are forces, moments, or masses that act on nodes.

In the list, select the 'Load Case' to which you want to assign the load.

Main

The Main tab manages the basic load parameters.

Categories

The following options are available in the 'Load type' list:

  • Force: The load is a directed quantity.
  • Moment: The load is a product of force and lever arm.
  • Components: The force or moment can be described by portions of the quantities that refer to the axes of the global or user-defined coordinate system.
  • Mass: The mass is the property of matter for Dynamic Analyses.

Important

To consider a mass in the calculation, activate the Active mass option in the 'Static Analysis Settings' dialog box (see the image Basic Settings ).

If the nodal load does not refer to the global 'Coordinate system' XYZ, you can select a user-defined coordinate system or create a new one.

Select the 'Load direction' from the list to define the effect of the load. The three global axis directions X, Y, and Z and the directions U, V, and W for user-defined coordinate systems are available for selection.

Parameters

Specify the load value of the force, moment, or mass. For the 'Components' load type, you can prorate the load values.

Info

A positive moment acts clockwise about the corresponding positive axis. The global axes of coordinates in the work window help you to define the sign.

Options

Use the check boxes in this dialog section to define further properties of the nodal load. Depending on the selection, the Specific Direction, the Force Eccentricity, the Shifted Display or the Import Support Reaction tabs are added.

You can affect the display of the load vector by the 'Display on opposite side' option.

Specific Direction

The Specific Direction tab allows you to orient the nodal load independently of a coordinate system.

Select the 'Direction Type' from the list. In the 'Parameters' dialog section, you can then rotate the load about the axes X, Y, and Z, direct it to one or two nodes, or arrange it parallel to a member or a line. Select the reference objects graphically with the Select Individually button.

Force Eccentricity

If the load does not act directly on the node, you can specify an eccentricity in the Force Eccentricity tab.

Enter the 'Eccentricity Ordinates'. The distances refer to the global directions X, Y, and Z. In the case of a user-defined coordinate system, the eccentricities are related to the rotated X'Y'Z' axes.

Info

When calculating according to second-order or large deformation analysis, the load keeps its globally defined eccentricity. It is not adjusted to the node's rotation.

Shifted Display

In the Shifted Display tab, you can make settings to improve the display of the nodal load.

In contrast to a Force Eccentricity, the load is shifted only for the graphic display. There are no additional moments. Specify the 'Offset' in the global direction(s).

Use the 'Size/Distance' text box to adjust the display size of the load arrow.

Import Support Reaction

The Import Support Reaction tab allows you to import the support force or the support moment of a node from another model as a load. For example, you can analyze 2D floor slabs by transferring the loads from floor to floor.

Tip

FAQ 5363 describes an example of how you can transfer support reactions from another model.

Import from Model

In the 'Model Name' list, select the model from which you want to import a support reaction ("original model"). This model must be located in the same Dlubal project and must have a different model ID (see the Model Parameters ).

Import from Loading

All load cases and load combinations available in the original model are available for selection in the list. Result combinations and design situations are not available because enveloping support reactions cannot be imported. Use the list button Filter List to filter the entries (see image above).

It does not matter whether the results of the load case or the load combination are available in the original model. During the calculation, the relevant results are determined automatically in the background.

Info

The reaction load is linked to the support load of the original model. Subsequent changes in the original model are automatically adopted in the target model. This way, you can interlink models of the same project.

Import from Node

In the list, select the number of the supported node whose support force or support moment you want to import. With the Load type in the 'Main' tab, you can define whether a force or a moment is imported.

Load Direction

Select the global axis whose component of the support reaction is to be considered during the import.

Tip

To import all load components, select the Components load type in the 'Main' tab. Then, the All option is available in the Load Direction list to determine all load directions.

Parent Chapter