Displacement boundaries/External loads

This tabbed pane concerns the input about displacement boundaries and external loads.

You can select the direction of the restraint/load by means of the radio-buttons.

You can choose between operating on faces or points. (Points are only used for point supports)

You can assign the same model to several surfaces just by selecting the surface by clicking the left mouse-button. Dragging the mouse over surfaces with Shift and left mouse button pressed, copies selection/deselection to the surfaces.

To position the structure in the right angle, you can turn it by means of the scrollbars, the arrow-keys or keep the left mouse-button pressed while you drag the mouse.

You can zoom in on a specific part of the structure by dragging the mouse with the left mouse button kept down, while the Ctrl-key is pressed. Zoom back out by clicking the right mouse button. Also, the mouse wheel can be used for zoom/unzoom.

By means of the keyboard all surfaces on a specific volume or on the entire structure can be selected, see Overview Mouse and Keyboard actions

If no structure is present, create a new volume by means of the "New Volume" in the upper left window. Before that you have to make a material which can be assign to the volume. Use the button "New Material".

Supports:

If the user does not specify boundary conditions which makes the structure statically determinate, the software automatically makes the necessary complements. However, this could be inconvenient if the user wants to examine the displacements. In that case the user can specify point supports. When point supports are specified, b4cast does not add the necessary supports if the structure is statically indeterminate.

Faces:

For future purpose a model with a prescribed displacement is shown.

At the moment only the prescribed displacement "0.0" is implemented and because of that, the fields in the table are not editable.

Stress-analysis is time-consuming. Therefore it is a good idea to make use of symmetry. In planes of symmetry the displacement normal to the plane is zero.

When calculating axisymmetric problems it is only necessary to model a wedge with the appropriate restraints normal to the sloped surfaces.

Points:

In Point mode are shown potential points for support. Supports are turned on/off by clicking near the blue circles. The direction of the support is selected by means of the radio-buttons.

External loads:

The time-load relation is representing the external load acting on the selected surface(s).

The external loads are also useful to describe a “plastic” support when self-weight is involved. If loads equilibrating the self-weight are specified no external supports are needed and stress-concentrations could be avoided. When no supports are specified the software automatically makes the necessary complements. In that case, unsuitable results are obtained if the resulting load from self-weight and external loads are differing from zero.

Now it is not possible to define point loads.

By means of the "previous"- and "next"-buttons you can see how the structure is at the times where casting takes place.