Join Josh Modglin for an in-depth discussion in this video Creating sample lines and sections, part of AutoCAD Civil 3D Essential Training.
- [Instructor] Now that we understand the relationships that exist between alignments, sample lines, cross sections, and section views, let's go ahead and create our sample lines and, really as a result, create our cross sections. So we're going to open up our drawing here, our 0-9-0-2 sample lines exercise file. We have our corridor as well as our alignments. And from the home ribbon, under the profiles and section views panel, the middle option is to create sample lines.
So I'm going to go ahead and select that. It asked me to select an alignment, because there's so many objects here, we have a corridor, we have labels, we have surface. I'm going to choose the other option of pressing enter to select the alignment from the list. The alignment we're looking for is Ossiola Road. We click okay and it says well, there's not an existing sample line group. So I'm going to make one for you. Again the sample line group gives us the ability to make quick changes, such as what data sources to sample for the entire group of sample lines associated to the sample line group.
The style, the default style to apply to all the sample lines, layer, and so forth. Currently in the drawing we have three different types of data sources that we can sample. We have the existing grade surface; you can tell that from the icon as well as the name. Because it says surface it applies a section style. And because it's existing grade, we're going to change the layer for that to being existing grade for our sections. The next type we see here is, we can actually sample a corridor.
Because we're sampling a corridor, it doesn't use a section style, but rather a code set style. Similar to how we would create an assembly. We're going to use a code where the code's associated to the points, links, and shapes, and be able to colorize and shade them accordingly. We're going to change this style to being IM Print. Lastly, the other data source that is available to sample, is a surface, but is a corridor surface.
So it's kind of a blend of two symbols there. We're going to sample that, but because it's a surface, it's a similar section style to the EG. We're just going to apply a different layer to it. So everything is set up for our group. We still haven't created any sample lines. The command line's asking me to go ahead and pick a station. I don't want to have to pick. Can you imagine, on a five mile road, how many times you'd have to pick to add a station? So we're going to look at the other methods to add sample lines along this linear path.
You can select existing polylines. Very useful when you may be creating cross sections along a stream or river, so as to properly follow the banks. Now that would be the only time you may have a cross section that I've seen in production where it doesn't follow perpendicular to the alignment or linear path. So a perfect reason to create a polyline and then select those picking points on screen.
We can use the corridor stationing. In other words, every single time the corridor applies an assembly at frequency, it would create a sample line. If you look in the drawing there, all those magenta lines, that's a lot of sampling. By default, it's going to pick add a station, but most of the time the easiest way is by a range of stations. So we select that option. And it says alright, tell me the range. You want to do it from the alignment start? Actually no.
If you notice my alignment start is where these two roads come together, I really don't have my design starting right until maybe 50 feet in. So we're going to set our start station at 50. But we will go to the entire length, to the end. We're going to snap to the alignment for the left? No. We're just going to type in general numbers for the width. But this is really neat. If you're right-of-way or your swath width that you want for the left or the right, you want it to vary and adjust depending on the needs, you can create alignment that it will follow and snap to for your sample lines.
How often to sample? We're going to use sampling increments. We're going to snap to the absolute station, 100, 150, and so on. And this is how often we increment. Generally speaking, I rarely see it where it's going to be more than on a curve than a tangent. Usually it's a set number. Every 25 feet, every 50 feet, something like that. Do you want to start at the range start? Yes, and go the full length. Do you want to include horizontal geometry points? Do you want a sample line at the PC and PTs? No, we'll just stick with every 50.
And that's the same for any super elevation critical points as well. Go ahead and click okay. And it drew all those sample lines. You see the turquoise lines there? And it continues to ask me to add additional ones. I'm done, so I go ahead and press enter. It completes the command. This is when the sections are cut. So it takes a second or two as it creates the sections. It doesn't look like anything occurred, but you see the sample lines drawn. More than that, if we go to prospector here, under alignments, under center line, we go to Ossiola Road and our sample line group and go down through and look at our sections.
Now let's just pick EG here. Look at how many sections have been created. So all those sections are ready to be shown. We simply need some section views to draw those sections. Well let's see how we do that in our next exercise.
This course gets you up and running with AutoCAD Civil 3D. First, instructor Josh Modglin shows how to model a surface, lay out parcels, and design geometry, including the making of horizontal alignments and vertical profiles. Next, Josh demonstrates how to create corridors, cross sections, pipe networks, and pressure networks. Then, he covers working with feature lines and grading objects, and how to share your data. He wraps up by providing an overview of plan production tools.
- Navigating the Civil 3D interface
- Using point groups and description keys
- Importing survey data
- Managing figures
- Creating and analyzing surfaces
- Creating parcels
- Working with alignments
- Working with profiles and profile views
- Working with assemblies and subassemblies
- Creating Basic and Advanced Corridors
- Using an Intersection Object
- Making sample lines, cross sections, and section views
- Creating a pipe network
- Understanding pressure parts
- Creating and editing feature lines
- Creating and editing grading objects
- Sharing and referencing data
Skill Level Beginner
Some of the exercise files do not properly function.
This course was built to work with the latest release of AutoCAD Civil 3D. If you are not running AutoCAD Civil 3D 2018 there are some exercise files that will not work for you.