The Power of Design and Change: Best Practices for Conceptual Design
I spend a lot of time around good AutoCAD® Civil 3D® users, folks that ask me tough questions about how to expand the usage of existing tools to solve new problems. Through this process I’ve learned to think of corridors as more than “long, linear design objects,” points as more than “X,Y,Z,” and surfaces as more than “existing or proposed.” Out of this rises a challenge I continually pose to engineers and landscape architects: digitize your conceptual design phase. For the record, Figure 1 is an example of what is not digitizing your conceptual design phase (i.e., an aerial image with hatching).
Figure 1: Non-ideal concept plan
Why?
Digitizing your conceptual design phase is less about creating stunning 3D visuals (which, of course, are very nice) and more about using a tool you already own to create a better process throughout the course of your project. That is to say, it’s all about starting right. Why is this the “right way” to start? Digitizing conceptual design leads to less data loss between design phases. Currently in our world, most professionals conducting conceptual design have extensive industry experience, but very little CAD experience. This means that most firms are creating with a pen and digitizing. This process immediately removes years of design experience from the design being created, and begins the digital process of a project on the wrong foot.
Am I advocating training everyone that does conceptual design on all the facets of Civil 3D? No, most of that stuff is for construction document creation. What I’m advocating for is digital involvement throughout the course of a project. Just as projects are more successful when all team members are involved in initial planning, so are projects more successful when technology is part of initial planning meetings. Understand how to push Civil 3D to create your conceptual designs—take your firm from using pen and paper (with all design validation in one person’s brain) to a design process that instantaneously validates design ideas as buildable and desirable. Save yourself from data loss. Figure 2 is what I want to see from your conceptual design phase:
Figure 2: Concept plan using Civil 3D effectively
That’s Great, but HOW?
First, having good CAD standards (solid templates, good data management practices, etc.) eases this process a great deal. If you’re not working with a good template, spend the time to make it right or hire someone to make it right. You’re wasting time every day if you’re not working with a solid template. Is one template the way to go? Maybe. Should I have a conceptual design template? Sure. Should I start from an empty file? Yes. Should I start from acad.dwt? NO (there’s a known issue). There’s much knowledge in this area, and every organization is different. Decide what works best for you, or ask someone knowledgeable what you should do. There are a number of different tactics that I believe work best for creating conceptual designs in Civil 3D and they vary by company and project.
Second, conceptual design is not creating construction documents. The minutia must be removed. The desire/concern for perfect, beautiful, and fully functional drawings needs to be lessened. The name of the game here is speed and validation. You want to use Civil 3D to make the conceptual design process faster, not make the conceptual design process inclusive of your entire design. You want to use Civil 3D to infuse conceptual design with validation, not spend three days during the conceptual design phase revising cross sections.
Third, create everything with deletion/modification in mind. The old adage applies: the only thing final about a conceptual design is that it’s not final. Everything will change, so use Civil 3D tools to create the objects to change as easily as possible, and know what it means to change these items and learn more about the tools to edit and create. Let’s look at some tools you may already know well, and show how to utilize them for conceptual design.
Housekeeping
General housekeeping strategies allow for consistencies between designs and, therefore, a more efficient design path. One of the most commonly overlooked general strategies is as follows: if you’ll use it more than once, name it. For example: you want to present 50 ft, 65 ft, and 75 ft wide lots to your client. You needn’t use three files for this—use one with Sites named accordingly. This will allow you to have different styles set up, and therefore have plotting pains eased as well.
Figure 3: Sites named according to lot size
Layout
There are numerous tools to ease this process, but the most overlooked is Sites. Sites are essentially containers that tell Civil 3D what objects should interact with each other. Want to show parcels of different sizes in the same drawing? Use a Site for each, as in my example in Figure 3. Sites also allow you to have Grading Groups that do not interact with each other, but grading and layout components that do.
Pro Tip: Use the ability to move and copy design objects between sites to ease non-geometric revisions, or utilize a previous design’s information for future designs.
Figure 4: Sites example
Civil 3D Parcels allow designers to very quickly develop and manipulate layouts. In addition, Parcels offer immediate feedback about sizing information for different layouts. This makes a particular impact when utilizing the Parcel Layout Tools. Designers involved in single-family residential design will find these particularly useful to their workflows during concept. For commercial and mixed-use design parcels, offer a quick alternative to manual “bubble diagrams”—set up a few different styles so you can quickly apply them across and keep close track of acreage per use.
Parking is often an issue for commercial and mixed-use projects. That is to say, much of the concept stage is spent determining the following question: with this architectural footprint, these existing conditions, and regulatory requirements, how many parking spaces can I fit or do I need? However, the reality of laying out parking is that it’s time consuming. Using the MEASURE command and arrays can help this process. I’d be remiss if I didn’t say here that Autodesk Vehicle Tracking software is a more desirable path and will ease this process greatly. Set up your standards and layers, and go.
Pro Tip: Learn the grips; they help immensely.
Figure 5: Parking generated from Autodesk Vehicle Tracking (grips shown)
Dynamic and Multiview Blocks offer some very quick and easy methods for conveying design intent and allowing for rapid changes and 3D views of plan view items, respectively. The concept here is to use pre-created blocks with rapidly modifiable properties in order to maintain as much dynamic and changeable content in your conceptual design as possible. See Walt Sparling’s coverage of this in AUGIWORLD, June 2014 for additional information. As an extension, effective use of Tools Palettes helps here a great deal.
Grading
While we’re on the topic of tool palettes, there’s a great deal here that can be created in order to produce Quick Corridors (like common assemblies). By “Quick Corridors” I mean “Grading Studies.” Grading during the conceptual phase is, without question, the most time-consuming of all activities. To add to this, the decision to continue a project is often made during grading studies happening during the conceptual phase. Using Corridors can help this process a great deal. Have to complete a mass grading exercise? Use a single Alignment to represent the outer extents of your developable area and use a daylight subassembly to look at different possibilities.
Pro Tip: spend some time and learn the subassembly composer; you’d be surprised how similar different grading exercises can be and creating your own subassembly can save much time on future projects.
Figure 6: Mass grading using a Corridor (conditional assembly example)
Using an Alignment and Profile allows for much better representation of the proposed conditions. This is particularly true with the new profile editing tools in Civil 3D 2015—specifically the ability to lock a profile to an alignment, and the ability to parameter lock/unlock geometry in the vertical profile. I’ll admit this takes some practice; however, if you stop and think about how you design with your pen and trace paper and use that same philosophy to design using Civil 3D you’ll master it in no time.
Pro Tip #1: Don’t forget about the Help entries for subassemblies—they are great!
Pro Tip #2: Learn your Transparent commands. They allow you to create profiles with ease.
For more complex grading, Grading Groups and Feature Lines are your best strategy. I could write an entire article about this topic. The strategy here is fairly simple, but again takes practice to master. First, use a single feature line to define a major grading requirement (a finish floor, for example). Second, use a grading group to define a relationship and create a surface. Third, create a feature line that is draped over this surface to begin creating more precise geometry. This strategy allows you to let the computer do what it’s good at (math), and you to do what you’re good at (design).
Pro Tip: Set your Feature Line double-click action to be the Quick Elevation Editor.
Land development is tricky; every project is different. Not only that, but every municipality is different, and every manufacturer has different specs. This makes using a feature such as Families in Autodesk® Revit® impossible for civil engineers and landscape architects. Luckily, we can lean on Grading Criteria to allow us to ensure regulatory compliance where practicable.
The most common use here is with water quantity or water quality controls. Ponds represent an area where there is often reproducibility and consistency, not to mention an oft-changing boundary condition. Here I like to have in my template some Grading Criteria that are locked where regulatory requirements must be met, and editable where they are able to be. Setting these up in advance, specifically in municipalities of common work, allows for much less time utilized during project concept planning, and higher accuracy once grading begins.
Pro Tip: Using dynamic Feature Lines from a Corridor allows for this process to be even more dynamic.
Figure 7: Pond graded with Grading Criteria set
Now, Go Try it!
It’s your turn. Experiment with these tools and workflows, figure out how they work, determine their best uses, understand how to have the highest impact on your conceptual design process. Often you aren’t being paid during this time anyhow. Become more efficient, spend less time in concept, change your mind often, incorporate client input, present your ideas, and (most importantly) validate your design concepts before you travel down a path that will not work! Good luck.
