Building a Custom Assembly with Baseline and Sub-Assembly Pieces in Civil 3D

Now that we've placed a common assembly, we're going to go ahead and build a custom assembly using a baseline and some sub-assembly pieces. So in order to do that, we're going to go ahead and navigate up to assembly.

We're going to go ahead and select create assembly, and we're going to get this create assembly window. I'm going to be creating an assembly based on my dev main and dev branch alignments. So I'm going to go ahead and name my assembly dev.

I'm going to go ahead and not place a description. I am going to select an assembly type for undivided ground road. You do have options for the different types of roadways that you can have here.

So you have the two different kinds of undivided roads, you have divided roads, you have railway, and then if none of these apply, you have other. So moving on from here, I'm going to go ahead and select basic assembly style, since we only have one option here, and I don't want to go in and create a new one. We can take a look at this assembly style at a later date.

But moving on from there, I'm going to go ahead and do a code set style. I'm going to choose all codes because I want to have all the codes present when we start looking at the different assembly pieces. And then from here, we have the assembly layer.

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I'm okay with it being on C road ASSM. So I'm going to leave it as is. I'm going to click okay.

And what Civil 3D is going to prompt me to do is to place my assembly baseline location. Since I'm going to be using this assembly for both my main alignment and my branch alignment, I'm going to go ahead and place it in between the two profiles that I have here. I'm going to zoom in, I'm going to click, and then Civil 3D is actually going to zoom me in further so that the baseline for my sub-assembly is centered in the and of a size that's easy to work with.

So from here, I'm going to go ahead and go up and turn on my tools palette. And then I'm going to navigate to the basics tab. We worked in the assemblies tab before where we had the common assembly basic assembly that we placed over on the other side of the drawing.

I generally prefer to work in this basics tab because they do have a lot of pieces that are available to create a road. If there's something here that's missing that you need, the individual sections for lanes, shoulders, and medians, and so on and so forth are below. But I find myself more often than not working inside of this basics tab.

So I'm going to go ahead and start with my roadway, creating a basic lane. I'm going to select basic lane. And what you're going to notice here is that Civil 3D brings up a new properties window.

So inside of this properties window, you have generic information for your assembly piece or your sub-assembly piece. But the important piece of information that we have is down here in this advanced parameters section. We have options for this basic lane for a side, a width, a depth, and a slope.

Now, these advanced parameters will change based on the different sub-assembly pieces that you select. If for some reason something that is inside of these advanced parameters doesn't make sense or you don't know what they're asking you for, the way that you can find out what they're asking you for is you can go over to your tool palette. You can right click on the sub-assembly that you're trying to use, and you can select help.

When you select help, Civil 3D will bring up a window that will give you a nice picture of what the sub-assembly piece is. It will show you what these parameters are, width, slope, depth. It will also give you information on what the input parameters are.

So which side, what width, what depth, what's percent slope. It will give you the type of input that you need, and it will give you the default values that show up when you select that basic or that sub-assembly piece. Moving on from there, it'll also show you what your targeting conditions are, what output parameters you can give.

It will give you the behavior of that sub-assembly piece. It will tell you about the layout mode. It will show you the point, link, and shape codes.

So each assembly is based on certain points, links, and shapes. So you can see here in the coding diagram that this sub-assembly piece is made out of points 1, 2, 3, 4, lines 1 and 3, and 2 and 4. Then you also have shapes, so S1. So these are the codes that will be output, and you have locations for them.

So P1, P2, P3, P4, L1, L2, L3, L4, and S1. And these are basically the point on this corner, the point on this corner, and going around, then we have the lines that make up the shape, and then the actual shape inside of our lane. So I'm going to go ahead and close this window.

I'm going to select basic lane. I'm going to go ahead and build it going from the center to the right. So I'm going to go ahead and leave this side as right.

I'm going to change my width to 17 feet. I'm going to leave my depth and my slope the same, and then Civil 3D is going to prompt me to select a marker point within the assembly. So what I'm going to go ahead and do is select anywhere on my baseline to start the creation of my assembly.

What Civil 3D does is it places my lane on the baseline building to the right, and it will build this piece out 17 feet with a depth of 0.67 at a slope of negative 2 percent. So moving on from here, I'm going to go ahead and choose a basic curb and gutter. I'm going to go ahead and make sure I'm continuing to work from the right.

I'm going to have all of the rest of the parameters remain the same. So 1.5, negative 6, 0.75, 0.5, and 1.5. And now what Civil 3D is asking me to do is to select a marker point within the assembly to place this curb. I'm going to go ahead and place it on the edge of my road at the top.

So I'm going to pick up here, and Civil 3D places my curb down. Now I'm going to go ahead and go to a sidewalk. So I want to place a basic sidewalk.

I'm going to select basic sidewalk. And inside of here, I have the options for which side I want to go to. I'm going to leave it as right.

I'm going to go with width. I'm going to leave it as 6. We're going to go ahead and leave it as 0.33 for our depth, and we're not going to have any buffers. So I'm going to go ahead and pick the location where I'd like to place this.

I'm going to go ahead and come up here, select this point. Civil 3D will place my sidewalk in. So from here, I'm going to go ahead and now choose how I'd like to grade this assembly out to a surface.

So I'm going to go ahead and select basic side slope cut ditch. I'm going to click in here, and we're going to see a lot of parameters inside of here. So you can see here, we have a lot of different conditions that can happen when we're creating this.

We have cut conditions and fill conditions. We have drainage swales that can be added. So what I'm going to go ahead and do is go into this basic side slope cut ditch.

I'm going to right click, and I'm going to select help. So inside of this help here, it's going to show us what the different parameters are. We have a case one and a case two cut and fill conditions.

So in our fill condition, it's just going to grade to a daylight surface. In the cut condition, we have the options for a four slope width, a bottom width, a back slope width, and then our cut slope, and then the daylight to the surface. So what I'm going to go ahead and do is look down here at what the different input parameters are.

So I have sides, daylight link, cut slope, fill slope, four slope, slope, four slope width, bottom width, back slope, slope, back slope width, rounding options. So a lot of these, I'm going to go ahead and leave as they're defaulted, but I am going to go ahead and change some of these four slope, back slope, and bottom width information, because in my cut condition, I don't want to place a swale. I just want to grade to the surface.

So I'm going to go ahead and leave it as such. So what I'm going to go ahead and do is close this window, select basic side slope cut ditch. I'm going to navigate down to my advanced parameters.

I'm going to go ahead and change my widths. So I'm going to look for my four slope width. I'm going to click in here, hit zero.

I'm going to look to my back slope width. I'm going to go to four, change it to zero. I'm going to go to my bottom width, click on this two, change it to zero.

And then what I'm going to go ahead and do is I'm going to go ahead and hit ENTER to accept that zero. Then I'm going to navigate over to the window and select the marker point within my assembly. I'm going to pick this point up here and Civil 3D is going to put in this marker for cut slope layout mode and fill slope layout mode.

So I'm going to go ahead and hit escape. Now I could go back and build a lane to the left, a curb to the left, a sidewalk to the left, and then a cut slope and fill slope to the left. Or what I can do is I can drop a window across these three items and up in the contextual ribbon bar, I can choose mirror.

I can select the marker point within the assembly for where I'm going to mirror this. I can select my baseline. And then what Civil 3D does is it takes everything that was to the right and mirrors it to the left-hand side.

Now that we've created this, I'm going to close out my tool palette. I'm going to zoom back out so you can see how large that cross-section is. And then I'm going to center this up.

I'm going to save. And I'll meet you in the next video.