This is the third article in my series on BIM. If you haven’t done so yet, your should read the first two sections: “BIM From The Ground Up” and “Existing Conditions In BIM.”

So, we’ve created our initial concept and prepared our existing conditions with the help of programs such as Autodesk ReCap and InfraWorks, but now we’re ready to begin the detailed design process. Where does the Building Information Modeling (BIM) process begin in the design world?

Well, at the same place a design project has always begun: in the ground! Both products mentioned above can export their data out for use by any number of Autodesk programs. That would include AutoCAD Civil 3D, which is the premier program for beginning any infrastructure project. To get your concept out of InfraWorks and into Civil 3D, you export it as an IMX file and C3D has an “Import IMX” option on its Insert ribbon bar. The data you pull over comes in as fully defined surfaces in your Civil 3D drawing, ready for you to begin working with. The same is true of your point cloud data from your reality Capture or LiDAR scans, they can be imported directly into C3D as: Point Cloud Objects through your Prospector tab.

Think about that for a moment. You are beginning your design process with an approved layout and highly accurate existing conditions and instead of spending days creating those, you’ve imported them in a matter of minutes. Now, those initial imports are not perfect by any stretch of the imagination, if they were, we wouldn’t need to bring them into Civil 3D at all.

What the BIM process has done for us here is all the heavy lifting. We get to bypass roughing out our 3D model and move directly into the fine tuning process. I’ve worked projects where that would mean the difference of two weeks billable time for several designers. Numbers like that are hard to ignore. With this data already in place, I can use native C3D tools to generate alignments from the surfaces, as well as profiles, cross sections, etc. to start fine tuning my design.

So, you may be asking, what crazy stunts do I have to pull to make my Civil 3D design a “BIM Compliant” design? Well, that’s the beauty of it – you really don’t need to do anything. All the 2014 versions of Autodesk vertical design packages (C3D, Revit, AutoCAD Electrical, etc.) are all fully functional BIM modeling packages. The very tools that you use on a daily basis to do you current designs are already generating the BIM information you need, you just didn’t know it! Consider an object from Civil 3D, such as a storm drainage system. Your basins and pipes are all placed (automatically) by the program as 3D objects, with actual size, parameters, and geographic locations when you place them. Even if you’ve never paid much attention to it, if you look at the details of your pipes you will find parameters for wall thickness, pipe length, material type, etc. that can be read for BIM purposes. Your Civil 3D systems (corridors, pipes, parcels, etc.) are all three dimensional objects with extended metadata that form the basis of a BIM system. Most infrastructure firms are only using those objects for their parametric capabilities within their own design project (i.e. changes to one object updates related objects) but these components can be shared across the entire projects, becoming the basis of the entire BIM. Architects can place their building design in real world locations based off the civil design file, underground utilities can be coordinated and verified for proper connection before going to field, landscaping tree locations, grading, and a hundred other items can all be verified in the virtual world.

The civil design site in BIM can be tied to scheduling, materials pricing, cost estimates and even updated with as-built information as each trade completes their work so that there are almost no conflicts or change-orders required during the construction process. Each successive trade can verify the location, size, and specifications of every object in the virtual model before they send a single crew to the site. This level of detailed design can also be used as output for advanced technologies like Machine Controlled Grading that dramatically reduce construction costs and error. All too often, I hear folks in the civil world discount BIM as: “Not important to us.” They feel it’s for the architects and owners but they are very wrong. BIM can easily cut design time and costs for your projects by 30% or more and give you capabilities you’ve never had before. Those can be offered as additional services to your clients that your competitors don’t have yet and that can help you win work!

I’ll continue with the BIM process in my next article: “Putting the ‘B’ in BIM”