Create topography from a CAD file

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The top I surface is a representation of the ground around the site.

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And maps will often show contour lines to

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indicate the elevation and slope of the ground.

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And drawings will often display spot elevations in plans

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to show the height at specific locations.

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It is important to have an accurate Toppo surface modeled for a site

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as it will influence the exact layout and location of the building.

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And here we can see we have some

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buildings modeled but there's no topography modeled around them

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to create a top by surface. For this. We'll use the contour data in a CAD drawing

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that needs to be linked into the project.

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So first

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from the project browser, we'll open the site plan view

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and now we'll go to the insert ribbon tab

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and from the link panel, we'll click on link head.

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Now you'll need to browse to where you have the exercise files saved

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and also like the DWG file site contours

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from the options at the bottom.

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Here, we'll uncheck the correct lines that are slightly off access option.

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This is because the contour lines in the DWG are all at varying angles

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and we want to retain any that are slightly off from horizontal or vertical

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in their actual drawn angle.

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For the position in here, we'll set this to be manual center.

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Now

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we'll click open

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and the site contours DWG will be linked into the file

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with the center of the DWG at the mouse cursor.

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And we just need to place it to this bank of contours here

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runs through the location of the building.

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Now we'll switch back to the 3D view

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and we can see the contours from the DWG.

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They are arranged in the 3D space and surround our buildings.

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No,

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from the project browser, we'll open the east elevation view

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and we can also see we have the contours visible in

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here and how they relate to the elevation of our building

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to create the Toppo surface. We'll first swap back to the 3D view

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and then from the masin and site

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tab

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on the model site panel, we'll click the top o surface tool

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looking at the edit surface ribbon. We can see that the place point tool is active

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and a topo surface is defined by individual points

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that are connected to create a triangulated surface.

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However, placing the points individually is quite a laborious task

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and hence having rev

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place them automatically along the contour lines in AD WG

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is the preferred option.

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So to do this

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from the tools panel here, we'll click the create from import button

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and then we'll choose select import instance

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now we just need to click on the DWG in the view to select it.

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And now we'll be prompted to choose the layers from within the DWG

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that contain the contours.

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So looking at the layer names here,

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we can see that we have one called contours and this is the only one that we need.

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So from the buttons on the right hand side,

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we'll click check none.

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And now from the list of layers here, we'll just recheck the contours layer

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and then we can click. OK.

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And we can see that the points have been traced along each of those contour lines

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and the top surface created

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zooming in a little closer. We can see the red lines of the contours in the DWG

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and the points that have been placed on those contour lines to create that surface.

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Due to the nature of the contours within CAD data,

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they can sometimes create multiple points that are very close together.

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And this can cause anomalies within the surface

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to help with this.

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We'll go to the edit surface ribbon and from the tools panel here,

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we'll click simplify surface.

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Now, we can see we have an accuracy setting of three inches.

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This means it will look within a three inch radius of each point.

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And if it finds other points, it will merge them together,

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we'll leave the accuracy set in as three inches and click. OK?

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And now we can see that the number of points has been reduced in the surface and

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they should give us a smoother surface to work with.

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So that finish is creating the topo surface.

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So from the edit surface ribbon here, we'll click finish edit mode.

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Now, the CAD drawing is still visible,

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we can see the red contours lines here and it

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makes it look a little bit confusing in the view.

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So we'll go to the insert ribbon tab and from the link panel,

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we'll click manage links.

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Now we'll go to the cab format tab where we can see the site contours DWG.

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So we'll click on this and then from the buttons at the bottom here, I'll click unload

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so that will unload it from the file and it will no longer be visible within the model.

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Obviously, if we needed to,

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we can always click reload to bring it back into the model.

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So I'll click. OK.

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And now we can see we have just the contours from the top post surface here.

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So to be able to control these, we'll go back to the

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mall and site ribbon tab.

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And from the model site panel here,

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we'll click to open the site settings.

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So in here,

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we can see we have our primary contour lines at intervals of 10 ft vertically.

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And below this here we have some secondary contours that are spaced every 1 ft apart.

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So we can click into this and set this to 2 ft.

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And when I click apply.

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Now,

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we can see that those contours are spaced every 2 ft and there's a lot less in the view

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equally. We could change the increment to six inches.

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And when we click apply,

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we can see we have a lot more contours spaced at six inches vertically. Now

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I'll change the setting back to 1 ft and we'll click ok

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to revert back to the original setting.

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And now we're swapped at a site plan view

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and we can see the top of surface in here

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with the contours being displayed as well.

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And it can be useful to have each contour labeled with its elevation.

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As this helps us understand in the plan,

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the slope of the ground around the building.

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So to do this from the mass

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and site tab

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on the modify site panel here, we'll click the label contours tool.

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And now all we need to do is draw a line through the contours that we want to be labeled.

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So we'll click here and then track in across right to the other side of the site.

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We'll click again

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and then straight away here, we can see that each contour has its elevation value.

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So starting at zero at the bottom and going up in one for increments here,

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that's gonna make it a lot easier for us to understand

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the slopes around the building when looking in the plan view.

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So we swap back to the 3D view

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and that finishes creating the top of surface for this site.