How to Model a Corridor in BricsCAD

Quick answer: A corridor models a 3D linear object like a road, railway, retaining wall, or bridge, built from a 3D alignment and a typical cross-section called a Corridor Template. CORRIDOR creates one, CORRIDOREDIT edits it, and CORRIDOREXTRACT generates meshes, solids, polylines, or boundaries from it.

About Corridors, Targets, and Target Mapping

When a template element’s geometry needs to follow a specific surface, horizontal object, or vertical object, you create a target and add it to the corresponding point on the template element. Three target types are available: Surface, Horizontal, and Vertical.

Once created, a target needs to be mapped from the Corridor Template Element’s point to the actual corridor model in the drawing, done by selecting the entity that represents that target. This is called Target Mapping.

Creating a Road Corridor

1. Open a drawing containing a TIN surface, a 3D alignment, a corridor template, and a Surface target already added to a template element point.
2. Launch CORRIDOR.
3. Select the 3D alignment to use as the corridor’s baseline.
4. Select the corridor template.
5. Enter a region start station, or press Enter to start from the beginning of the alignment.
6. Enter a region end station, or press Enter to extend to the end of the alignment.

Mapping a Target

Continuing directly from creating the corridor:

1. Select the corridor in the drawing.
2. Click the browse icon in the Target mapping field of the Properties panel.
3. Select the entity representing that specific target, the TIN surface, for example.

Editing a Corridor’s Position

1. Open the drawing containing the corridor.
2. Select the 3D alignment the corridor references, and move its grip points to edit the corridor horizontally.
3. To edit vertically instead, select that same 3D alignment, open the Properties panel, and set Update mode to Manual; extra grip points appear.
4. Move those extra grips to edit the corridor vertically.
5. Press Enter to finish.

Splitting a Corridor Region

1. Open the drawing containing the corridor.
2. Launch CORRIDOREDIT.
3. Select the corridor model.
4. Choose the Split Region option.
5. Select the region to split, by index, by name, or by selecting it directly in the drawing.
6. Select or enter the station where you want the split, you can specify multiple stations to split at once.

The original region splits into two at each specified station.

Replacing a Region’s Template Element

1. Open the drawing containing both the template elements and the corridor.
2. Open the Properties panel and click the corridor in the drawing.
3. Select the region whose template element you want to replace.
4. Click the browse button in the Template name field.
5. Select the new corridor template.

Extracting a TIN Surface from a Corridor

1. Open a drawing containing a TIN surface, 3D alignment, template element, and corridor model.
2. Select the corridor template element.
3. Select the template element link you want to use for extraction, hold Ctrl to select several.
4. Enter a code name, TIN, for example, in the Codes field under Link Data.
5. Launch CORRIDOREXTRACT.
6. Choose the TIN option at the Command line.
7. Enter the links to extract, matching the code name set earlier (type ? to see every available link code).
8. Choose Yes to add them as breaklines.
9. Enter another link to extract, or press Enter to stop.
10. Choose Yes to use the outer edge as the surface boundary.
11. Choose Yes to create a dynamic (live) link between the corridor and the extracted surface.

Corridor Display Properties

Select a corridor to see its properties, including five distinct display modes:

• Applied template points: shows the corridor via its template element points.
• Applied template links: shows the corridor via its template element links.
• Applied template shapes: shows the corridor via its template element shapes.
• Meshes: shows the corridor as meshes.
• Stringlines: shows the corridor as lines connecting template element points along its length.

Frequently Asked Questions

What’s the difference between a corridor’s horizontal and vertical editing? Both start by selecting the 3D alignment the corridor references. Moving its regular grip points edits horizontally; setting Update mode to Manual in the Properties panel reveals extra grip points for editing vertically.

Can I split a corridor region at more than one station at once? Yes, you can select or enter multiple stations during the Split Region process.

Does extracting a TIN surface from a corridor keep it linked to the corridor afterward? Only if you choose Yes when asked whether to create a dynamic link during the extraction process.

How do I see all the available link codes when extracting from a corridor? Type ? at the Command line when prompted for links to extract.