SS5 - Stretching / Altering Bay Sizes

With Interfering Elements

When a model is built, if for some reason the bay size needs to be altered after the miscellaneous steel has been placed, then altering the model may become a bit more difficult. The reason for this being that not all miscellaneous steel will react the way the user is expecting. One example of this would be bracing elements created using the commonly used dynamic bracing command. In this example bracing elements are parametric objects that are tied to the line or points originally selected when placing the elements.

Even though the parametrics of the object will allow for certain automatic updating functions to take place, radical changes like bay sizes may require that the parametric objects in question be replaced.

Using the bracing example mentioned above, the easiest method of doing this is to create a template from the parametric dialog window, remove the original elements and place them again using template to automatically setup the elements to their original state.

Cut lines or post modifications will also need to be repeated in this case.

Without Interfering Elements

If you do not have any interfering elements then a simple stretch command can be used to enlarge a bay area.  This will stretch the members in the selected area, along their current path to any length required. It should be noted however that if a workframe was used, then this will need to be modified afterwards from the workframe dialog window to match to new model sizes.

In a situation like this, stretching the elements along their existing path will simply enlarge the bay area without any adverse effects.

Three things should be kept in mind however when using this method.

  1. All items should be showing. Anything hidden or not showing for whatever reason will not be stretched.  Turn on layers that contain elements, ‘regen’ items that are hidden, display and area class objects should all be showing and clipping planes turned off. The use of any or all of these functions will cause the hidden objects to not be affected by the stretch.
  2. All objects will be stretched along their current path. If horizontal members are being stretched then this method should work fine but keep in mind that if something is angled that the members will not follow the horizontal shift but rather will continue to extend along their current course to the new point selected by the stretch command.
  3. The workframe itself should not be selected. The reason for this being that the workframe lines will be moved from its original location and not stretched. For this reason when selecting the elements to stretch, deselect the workframe lines before actually stretching the members themselves.


NOTE: The upcoming MicroStation version of SS6 may include code that allows the MicroStation stretch tool to better handle the stretching functions of ProStructures elements.