Civil 3D Corridor Management and Project DREFs

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Basic single Baseline Corridors require simple Civil 3D design control. Give me an A -a centerline Alignment. Give me a P – a centerline Profile. Give me another A - a full cross section Assembly. What’s that spell? Corridor.

Many basic Civil 3D Corridor web videos are kitten or puppy videos less the cuteness. They often seem to miss the point of the practical civil engineering design challenges that Civil 3D is so good at solving.

Civil 3D Corridor Templates

Civil 3D 2022.1 tools can greatly help improve and standardize the Corridor creation process. Corridor Templates rock because they can quickly match some commonly employed Corridor Properties from an external resource. The Corridor Template tool addresses some of the steps we must perform and apply time and time again.


New Corridor Templates and the Improved Match Properties Tool

Corridor Templates mean we have yet another Civil 3D Standards folder location and structure to consider.

  • Are there both organizational standards and/or Civil 3D Project-based Corridor Template standards?
  • What do our Corridor Template Standards drawings contain?
  • Do we need a prototype mini Civil 3D project with DREFs to help manage and maintain our Corridor Templates?
  • Can a DREF Corridor drawing be the source for a Corridor Template?
    Would we want to do that?

Be forewarned and forearmed that the Corridor Surface data content in Corridor Templates is highly dependent on the coding of drawing specific Assemblies and their collected Subassemblies that are employed in a Corridor’s Baseline Regions. Less can be more if we want generalized results.

These Corridor Surfaces data and results and the Feature Line Style dependent resolution of Slope Patterns speaks again for the need to employ consistent, robust, and adaptive Sets of Assemblies in Corridor development.

The integrated management of our Civil 3D Templates, Civil 3D Styles, Sets, and the many other Civil 3D resources matters.

We all end up with some form of Framework for Civil 3D. We take care of the silly details so you can get work done.

We discussed the details of the much improved Region -based Match Properties tool shown in part in the video in the recent Corridor Targeting Best Practices post.
The Multiple Baseline Corridors constructed in the Civil 3D Turn Lane and Median Corridors post and video benefited from these tools.

There is nothing simple about…

Managed Corridor Design Control in Civil 3D

Let’s face the fact the Civil 3D Alignments and their many children are the most complex and nuanced Features in Civil 3D. Yes. There’s an entire series of Book of Alignments posts available here.
Register and become a site Member. It is painless.

The Corridor collector may consume all the Alignments and their many children in all their subtlety and nifty nuance and thus produce some fancy, useful, a productive design results.

Let’s revisit the example of Turn Lane and Median Corridors in Civil 3D to explore how and why project-based Data References and Sets of Assemblies are mission critical to our productivity in Civil 3D.

“If you give the mouse a cookie, he will ask for a glass of milk.”


Shared Design Control and Multiple Baseline Corridors

As we see in the video, Project-based Data Shortcuts (DREFs) are essential for the development of Multiple Baseline Corridors and our production results for more than a few reasons.

A few Multiple Baseline Corridor issues are worth mentioning but not shown or discussed in the video.

  • Civil 3D appears to make the initial publication of Connected Profiles and Offset Slope controlled Profiles Static by default.
    These can be made Dynamic, but the results will be much more stable if there are displayed versions of these Profiles in Profile Views in the source DREF container resource drawing.
  • The use of the stock Civil 3D Generic Pavement Structure Subassembly requires that we employ a thought-out plan of named Link, Point (Feature Line), and Shape (Materials) codes to produce consistent useable Corridor Surface data results.
  • The Generic Pavement Structure Subassembly supports stacking these Subassemblies one top of another. Therefore, the above caution becomes even more important.
  • The Generic Pavement Structure Subassembly supports only a Shift out property. There is no Shift in.
  • Each Generic Pavement Structure Subassembly supports Superelevation - Apply it properly.
  • Sets of Assembly replacement methods work well for Assemblies with versions of the Generic Pavement Structure Subassemblies. In other words, it is relatively easy to produce separate grading corridor surfaces for lifts or stages of construction grading.
  • The tongue and cheek reference to GPS and machine grading control results based on Corridor Feature Line output results is intentional.

Multiple versions of Complex Corridors are often required due to the Region Station and applied Assembly Frequency nuances we encounter. Often another version of the Corridor with the same design control is the faster way to solve the problem. Can you say stake out?

Shared DREF Design Control

Here’s a summary about project-based and shared design control in Civil 3D from a most important post - Civil 3D Features Matter Most,

Civil 3D Features are mostly contained in drawings. However, a Civil 3D project is not a collection of drawings like a CAD project. The Civil 3D project is a managed collection of connected and/or disconnected Civil 3D Features. This current project Design State we call the Dynamic Model.

If we think of the Dynamic Model or Design State as something in a drawing, we have missed a most important fact.

The critical path task of Civil 3D Project Management is then about managing these critical Civil 3D Features and their interactions. At this point in time, the Feature interaction occurs inside drawings and/or within a one of the collector Features in a drawing.

Real-world, Civil 3D Users do the actual construction and connection work.
Therefore, a Managed Dynamic Model must be the real daily deal. Doing that well depends on people understanding and always doing that management work first.

It is far too easy to lose this sense of project priority and perspective inside a working Civil 3D project.

The Principles of the Separation of Powers

The principles and practices should help Civil 3D users accomplish the similar and related Corridor design work that is applicable to many more types civil engineering projects.

We must learn to employ classic Power of Names and Separation of Powers methodologies to create, edit, and manage all the interrelated data complexities of a Complex Corridor.

To review and summarize some of the Multiple Baseline Corridor Best Practices:

  • Project Data Reference (DREF) management of the design control is essential
  • Plan and Manage the creation of the Baselines and the Regions
  • Know Thy Subassemblies and their codes
  • Employ Sets of Assemblies to manage the cross section design control and Property details
  • Master the Region Create and Edit Tools and the Master the Corridor Targeting Tools
  • Corridor Surfaces are and are not generic Civil 3D Surfaces

Project DREF Management of Design Control is Essential

We recognize that a Corridor is an output and published results collector in Civil 3D.

All Complex Corridors include a host of horizontal, vertical, and cross section design control captured in collections of parent Alignments and their Children and those drawing specific Sets of Assemblies. It is way too easy in Civil 3D to attempt to manage and edit all that complex design control detail within a Corridor construction drawing.

In Civil 3D, a drawing-centric methodology always adds insult to injury or rather injury to the rather insulting and selfish concept of My Drawing. We must learn to employ Civil 3D in the wider and shared project data context to be more productive.

The Corridor engine will accept Feature Line based Baseline design control. Hoorah. This can be powerful and useful. However, Independent Feature Lines do remain drawing dependent.

The important exception to this rule is the Feature Line output of a Data Referenced Corridor.

The Civil 3D skills to convert and better manage that Feature Line Corridor output into shared Alignment and Profile pair Data References (DREFs) presently remain mission critical to our Civil 3D productivity.
See the Site Grading with Corridors video pages for more information and the post details.
See the final Data Reference mechanics video in the Cook with Civil 3D Corridors post for details.

The Darned and Crocheted Details Change and Exchange

It is almost always worth the time to create and maintain all that Civil 3D horizontal and vertical data behind in separate, Data Reference resource drawings.

This is a learned discipline and skill set in Civil 3D.

  • The use of DREFs matters significantly to Civil 3D stability and performance
  • The darned and crocheted together details can and do change
  • More available Options are always better than fixed unexpected consequences

See the substantive Civil 3D Data Shortcut Manager Tool post and video.
The capability to replace and update to separate, managed versions of a Corridor’s design control is a more than significant design and publishing benefit.

The previous Manage Sets of Assemblies in Civil 3D post and video explores how the methodology may be applied to the cross section design control which remains drawing specific.

Better Data Shortcut (DREF) management and the use of Sets of Assemblies allow us more systematic control of the current Design State.

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Complex Corridor Posts