Civil 3D Corridor Site Design Considerations

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We can employ Corridors to solve significant and common grading site design problems in Autodesk Civil 3D. We do need to acquire some skill and practice with Corridor design workflows. Corridor design methodology can be more productive than the classic Feature Lines only approach. After all, Corridors do produce and manage related Feature Lines in bunches.

That nifty trick alone says we should consider and take Grading Site Design with Corridors seriously.

The good news about Site Design Corridor is that Corridors will generally create a better managed and more flexible and adaptive design. We can achieve better design optionality for the same man-hour investment.

Site Design with Corridors

The bad news is that Feature Lines only methods are familiar ground for most long-term Autodesk civil product users. Linear based design from breakline primitives is a task most of us can do in our sleep. Our old friends work.

The complexity of a Corridor means we have more collected stuff to plan, to execute and edit, and to maintain. Why bother? Good question.

One of the common sense principals of a sound investment is that delayed gratification pays.
Site Design Corridors are a case in point.

The good news about Site Design Corridor is that Corridors generally create better-managed and more flexible or adaptive design. In other words, we can achieve better design adaptability and therefore more optionality for the same man-hour investment.

We must invest our time differently.


Site Design Corridor Considerations

Dynamic Offset Alignments and Widenings work well to help us solve many basic to advanced site design grading problems. This simple planar parking lot shows us the least of the potential benefits.

Site Design Corridors do require a more managed process and understanding of the nuances of the Civil 3D Corridor engine.

Recent releases of Civil 3D better embrace the use of our Feature Line friends in deeper design control roles. Newer releases have an improved Targeting and Corridor creation interfaces which allow us to more easily control and manage the Corridor.

Since 2018+, classic Corridor Alignment and Profile pairs are not the only way to generate Corridor Baselines. Feature Lines work as well. That doesn’t mean Feature Lines are easy to create, manage, and maintain in our site design project.

Yes. Civil 3D production work is always a Project.

Corridor Code Set Styles allow us to effectively produce the managed Sets of Feature Lines. We need both the Code Set Styles and the companion other Styles to make the processes and our design choices easier. The Framework for Civil 3D can help.

We Must Manage Our Lust for Detail

For many Civil 3D users, it appears that it is way too easy to get sucked into detailed surfaces from Corridors too quickly.

Many Civil 3D users tend to add details into the initial stages of the complex and multi-step design process that Corridors are best adapted to deliver. The quantity of detail that is potentially available from a Corridor model often can become simply overwhelming.

The video above clearly demonstrates that the Frequency properties inside our Site Design Corridors are particularly important for us to learn to manage effectively.

All too often more application of more applied Assemblies with their collection of Subassemblies and resultant Feature Line output creates unnecessary complexity problems for us.

If we find ourselves weeding extracted Corridor Feature Lines all the time, we might want to consider showing some restraint.

We don’t necessarily need or want lots of Feature Lines right now and right away. Here I mean both the number of Feature Lines and the Point Code related details in them.

The wisdom of when to apply the tool is as significant as the know how to do it.

Mission Critical Point Identification Benchmarks

In Corridor design, we want our design Assemblies applied in the most important and significant design locations. These mission critical points are important for Civil 3D users to learn to identify quickly.

No one said we must simply abandon tried and true our grade by points heuristics (method and practice) only because Civil 3D strongly favors linear methods.

An Assembly Never Works Alone

In case you never noticed, Assemblies always seem to run in packs.
See the Civil 3D Assembly State Management post.

Replaceable Sets of Assemblies are important design production tools we need to develop and maintain. Ok. We also need to learn the skills to quickly replace them on-demand in our Corridor Regions as the current design and/or publication need requires.

A managed project evolution from simple Sets of Assemblies to the more detailed Sets of Assemblies should become a new Civil 3D site design norm for Corridors.

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Grading with Site Corridors Posts

Updates, additions, and fixes to the posts in this series are on-going.