Welcome to the Family: The Transition to Civil 3D
Transitioning from existing technologies to new ones or implementing new technologies usually poses a challenge during the implementation phase for many reasons. If you are already familiar with the previous technology, in this case regular AutoCAD® as a drafting and design platform, the transition might be not so hard. However, if you are just getting familiar with the AutoCAD environment your learning curve might be steeper. But either way, transitioning to AutoCAD® Civil 3D® is worth the effort, and once you try it you cannot go back. I know there is more than one flavor of AutoCAD and I think regular AutoCAD will always have its place, but if you use it in civil engineering, land development, or a related field, then AutoCAD Civil 3D is for you.
Building on Common Ground
As a user of both regular AutoCAD and AutoCAD Civil 3D, I know about the transition and the learning curve that comes with it. I know it might be a little difficult at first and, just like developing many other skills, it takes training, time, and effort, but it is all worth it. So whether you are coming out of college or have many years of experience, let me talk to you user to user.
Civil 3D is built upon regular AutoCAD so you still need to maintain good CAD standards such as having solid templates and good data management practices. Templates in Civil 3D have more elements than the templates for regular AutoCAD. Therefore, whenever you start a project, use a Civil 3D template rather than the acad.dwt template because it doesn’t work well in Civil 3D.
Figure 1: Graphical user interface for AutoCAD
Figure 2: Graphical user interface for Civil 3D
Another big difference between the two programs is how data is managed within Civil 3D. For example, in regular AutoCAD the palette used most often is the Properties palette. This palette is also in Civil 3D and serves the same purpose, but Civil 3D also has the Toolspace palette. The Toolspace palette, along with the four tabs it has (Prospector, Settings, Survey, and Toolbox), is how data is organized and managed within Civil 3D. Once you start using it you realize that it is very intuitive and resembles how data is organized in some geographic information system (GIS) applications.
Figure 3: Toolspace palette in Civil 3D
Taking AutoCAD to a Civil Level
My background is civil engineering and construction management, and with that comes things such as design, drafting, and plan production. This makes me appreciate Civil 3D even more. So now let me tell you a little about some of the tools and workflows in Civil 3D for surveying, conceptual design, surface creation, land development, road design, pipe networks, earthwork, and more.
Civil 3D helps you work from field to completion. As you may know, in AutoCAD there are ways to import survey data and turn it into points that you can later use for drafting, but in Civil 3D you can do much more. For example, you can almost start drafting in the field while you collect survey data and assign codes to points you capture, then those codes tell Civil 3D what each point is—e.g., trees, hydrants, ground shots, fences, etc. All of this gives you a huge advantage when good workflows and standards are in place. The Survey tab In Prospector is where you organize survey data, create databases, and tell Civil 3D how to treat the data you bring in. In addition, when you work with the settings you find how you can start drafting as you import and process the data from the field while keeping the raw data intact.
Figure 4: Survey tab and survey database
Geographic Information and Elevations as the 3D Element
As we are talking about data, it is important to point out that the amount and quality of data you have will greatly affect the decision-making process and the planning phases of most projects. Sometimes the data collected by the surveying crew is not enough and you might have to look at some other sources. Civil 3D has GIS capabilities that help you make use of much of the GIS data available out there; this data is georeferenced, which helps put everything in context. Amid the GIS data in Civil 3D are aerial photographs that you can use as background images in your drawings, shapefiles representing road centerlines that you can turn into road alignments, shapefiles representing parcel boundaries that you can use for subdivisions, contour lines that you can turn into existing ground surfaces, and so on—all within the same program.
As the name suggests, Civil 3D uses the elevation component in the data to take drafting to a new level. The most common example of this is the creation of ground surfaces from point data—with just a few clicks you have a 3D representation of the existing ground conditions of your project based on survey data. Regular AutoCAD also has some 3D capabilities, but they are limited compared to what you can do with Civil 3D. This is particularly true in the context of land surveying and civil engineering because the 3D capabilities in regular AutoCAD are used mostly in other industries.
Figure 5: Surface created from point data
Urban Planning and Subdivisions
When you work in Civil 3D you use a combination of 2D and 3D objects. Let’s say that you are doing a residential development and you already have an existing ground surface, which is a 3D object. Now you want to determine the best layout for a given number of lots, common areas, and a retention pond you want to accommodate. You can do this by drawing lines and polylines, then you find the areas of the closed polylines and add text to label lots and common areas, but if the layout changes you do it all over again. Does that sound like a workflow you have seen before?
Civil 3D provides automated tools that can be used for subdivisions and urban planning. These tools calculate areas, add labels, maintain relationships between objects, split areas according to the user-given parameters, etc. The objects you work with are dynamic so if you make changes to the layout the rest of the objects change accordingly. In Civil 3D you use Sites, which basically are containers that tell Civil 3D what objects interact with each other. You can create and use different sites for different layouts, in each site you can have multiple Parcels, which in Civil 3D are closed polygons that can represent the original traverse and the proposed lots in your subdivision. Working with sites and parcels allow designers to quickly develop and manipulate layouts; they also provide immediate feedback about sizing and the interaction between objects. In addition to immediate feedback during the design process, you can apply different styles to your parcels. These styles can include specific hatch patterns to indicate what each parcel is, and by using styles you can keep track of areas and land uses in your development.
Figure 6: Parcels showing areas, distances, and bearings
Let’s Hit the Road
When it comes to road design, in AutoCAD you can start by using lines, arcs, and polylines to draw the initial geometry of the road you are designing, then add markers every 100 feet and labels—but if the geometry changes you might have to make some major adjustments to your work. As expected, Civil 3D has tools that specialize in road design, so whether it is for a residential development or new roads, as the city is expanding or the design of a freeway that connects two cities, you find a much more efficient workflow in Civil 3D. You can also start with traditional drawing objects such as polylines and arcs or import GIS features, turn them into AutoCAD objects, and then turn them into Civil 3D alignments. Alternatively, you can start off by drawing alignments from scratch.
Alignments in Civil 3D are dynamic objects used for horizontal geometry and include labels and markers for points or curvature, points or tangency, stationing, and so on. Because they are dynamic objects, you can confidently make changes to the geometry without having to worry that you will have to fix all your labels and markers.
Vertical geometry is another main component in road design and it is where the elevation data comes into play. Vertical geometry is drawn using profiles and, similar to alignments, they are dynamic objects that have markers and labels for points of vertical curvature, points of vertical tangency, etc. Civil 3D combines horizontal (alignments) and vertical (profiles) geometry in an automated way that facilitates the road design process. Profiles can also be used to sample an existing surface along an existing alignment.
Figure 7: Alignments and profiles for road design
Once you have the horizontal and vertical geometry for your road, you can take the design process a little further by using assemblies and corridors. An assembly is a collection of subassemblies, which are the basic building blocks of a roadway. They can be the typical components of a roadway such as lanes, curbs, shoulders, etc. A corridor is a path or road defined by an alignment, a profile, and an assembly. The combination of these elements creates a 3D object, or in this case, a 3D roadway that can later be used to create a finished ground surface that, in turn, can be used for earthwork volume calculations.
Figure 8: Corridors and roadways in Civil 3D
And speaking of earthwork calculations, we also have grading objects in Civil 3D. By definition, grading is the process of adjusting slopes and ground elevations. Civil 3D, being a 3D design program, handles this very well. We can create retention ponds, embankments, dams, and so on, or simply manipulate ground elevations for proper drainage in a parking lot, for example. Remember that the capability of using elevation data in the design process is one of the things that make Civil 3D the type of program it is.
Pipe Networks
Now let’s say you are still working on the same residential development that was previously mentioned and now it is time to design the sanitary pipe network. Again as expected, Civil 3D provides tools to accomplish these tasks in an automated way. You can turn existing lines and nodes into pipes and manholes or you can draw the network from scratch using pipes instead of lines and structures instead of nodes. You adjust the settings and select what kinds of pipes and structures you want and you are ready to go.
Because elevation data is a crucial design element, you can specify how deep you want to bury the pipes in your network and the slope of the pipes which, in turn, will determine invert elevations. Then you can add labels to pipes and structures to show elevations or other data already in them. When you make changes to the network such as raising or lowering a pipe, the labels update to show the new elevations. Now if you make changes to the pipe network imagine the time you will save when network components and labels are linked and update automatically. Furthermore, you can also show these elements in profile view and again, data and labels are dynamic and update as you make changes.
Figure 9: Pipe networks in Civil 3D
Cohesion
So far I have mentioned some of the common usages of Civil 3D and how objects are interrelated. The ability to use elevation data, the connectivity between vertical and horizontal geometry, the connectivity between corridors and surfaces, and the ability to annotate objects to show information contained within the objects are some of the features that make Civil 3D a powerful design platform where drafting becomes a by-product of design.
As mentioned before, Civil 3D is built upon regular AutoCAD so it has all the regular AutoCAD tools, which means that the good practices you already know in AutoCAD are still valid. External references and plan production work the same way; furthermore, you have data shortcuts that work similar to xrefs in the way they call data from external files.
Conclusion
There is much more to the program than what I can tell you, but I hope that you are starting to envision how transitioning to Civil 3D would affect the work you do and how it would boost your productivity. The tools that come with the program are powerful enough to accomplish many design tasks in civil engineering and related fields. When you add your own creativity and out-of-the-box thinking you can accomplish much more. After you start working with the tools you have at your disposal you will find that you cannot go back to the old ways. No matter how familiar you are with AutoCAD Civil 3D, whether you have just heard of it or are starting to use it, there is one last thing I want to say to you: welcome to the family!
Miguel Medina is a Civil Application Engineer for ProSoft, an Autodesk reseller based out of Utah. He has worked in construction management and design since 2008 and has implemented and trained companies on Civil 3D for the past year. Miguel can be reached at mmedina@prosoftnet.com
