OpenBridge Modeler Tip: Creating/Editing Point Constraints for Bridge Templates
When working with many of the OBM component templates, you’ll notice that the creation and editing of these specific OBM templates is similar to the roadway templates. We’ll use a deck template for this example.
When creating the template, you can provide constraints to a point and variable names to those constraints. This allows you to control these points when placing the template, and also after the deck has been placed. We will look at creating a point constraint.
Copy and Create a Deck Template
The Bentley-delivered WorkSpace will be used in the following example:
Copy a Deck Template
- Open the Deck Template dialog by going to OpenBridge Modeler > Utilities > Libraries > Decks
- Open up the folders to the Deck Slabs (Standard Templates > Deck Slab) and select Slab w/Constraints
- Right-click and copy the Slab w/Constraints template
- Rename it by right-clicking again – we’ll use “Slab w/Constraints 2”
Locate the Points and Their Constraints
In the bottom section of the Template Creation dialog, there are two tabs; one for the Point Details and one for the Key Points. We will be working with the Point Details.
There are two sections to the bottom – the Points on the left, which lists the points and their properties, and the Edit Details section on the right where the points details can be edited.
As with roadway templates, controlling the position of points in relation to other points is possible.
- Select Point P_1
- In the Edit Details section, you can edit the location of this point using one, two, or no Constraints
- Notice Point P_0 has no Constraints – this is the Working Point (WP) and it will follow the Alignment assigned to the bridge, while all other points are Constrained back to this WP
- Point P_1 is Constrained to Point P_0 horizontally by 20 design units (feet in this case) and is also Constrained to the WP by a slope of 2%
- Change a value, click the Save button, and notice how the template image reacts
- Change the values back to their original values
Introduction to the Variables
- Each of these Constraints has an associated Variable and can be used in the same way a roadway template Point Label can be controlled by a Parametric Constraint
- These Constraints and Variables can be edited as needed
Having a Variable for each Constraint allows for the control of the template points in the models using different tools. Point Controls and Parametric Constraints utilize Variables to adjust the Constraints values as needed. One example of how the Variable can be used would be if the Deck needs to flare out at one end of the bridge.
