Takeoff Tutorial

Lesson 2: Road Design From Start To Finish

This lesson takes a drawing file through the steps of road design.

Step 1 (Start Takeoff):

Click the Windows icon for Takeoff to launch the program. You may be presented with a “Startup Wizard” dialog and if so, click Exit.

Step 2 (Open Drawing):

From the File menu, choose Open and select DEMO2.dwg from the Takeoff Work folder (ie. C:\Program_files\Carlson_Takeoff_2004\WORK\DEMO2.dwg).

Step 3 (Existing Ground Surface):

For the road cut/fill slopes to be created, it needs the existing ground surface to tie into. First we need to define the layers of the existing ground surface. Run Tools-> Set Layer For Existing, pick on both a light-lined and heavy-lined contour, a spot elevation, and press Enter. This will set the layers CTR, CTRINDEX, and TO-PREM-SPOT-PNT to the existing surface. The limits of the site are defined by a closed polyline. Run Tools->Boundary Polyline->Set Boundary Polyline and pick the black polyline around the perimeter. This selected polyline is now set as the boundary polyline for the existing surface. To make the existing ground surface, run Tools->Make Existing Ground Surface.

Step 4 (Creating a Centerline):

Now we will use commands under the Roads menu.

Notice that the Roads menu is broken down into four sections: Centerline commands, Profile commands, Section commands, and Template commands. A road needs design input from all four sections to be created. It does not matter in what order the commands are run, but in this example we will run the commands in descending order.

A centerline file is necessary for the final road design routine. We will do the simplest variation, which is picking a polyline. There are other methods to design a centerline, and they are documented in the manual. Go to Polyline to Centerline File in the first grouping of commands under Roads. A file selection dialog will appear. Enter a centerline file name of demo2.cl and pick save. Follow the prompting:

            Beginning Station <0+00>: Press Enter
            Polyline should have been drawn in direction of increasing stations.
            Select polyline that represents centerline: Select the polyline that crosses the middle of the site with the layer name CLINE.
                 Station    North(y)       East(x)    Description
            ---------------------------------------------------------
                 0.0000 159718.2034 1857460.9166    LI
            1798.2055 159058.6315 1859133.7908    PC
            2912.2263 158347.2903 1859964.4134    LI
            3755.6840 157619.5351 1860390.7855    LI
            Press ENTER to continue.

Your Command Line should have the same values as these, as they are from the same line. Hit the F2 key or press Enter to return to the main screen.

Step 5 (Input-Edit Profile):

In this routine we will create a Profile file. There are different ways to define a road profile. In this case we will enter values from a given design. Go to Roads-> Input-Edit Profile File, create a new file, and name it Roaddemo. The Input-Edit Profile window will be displayed. Under Type of Profile select Road from the dialog box. In the spreadsheet, you can add design features for the Profile of the road. In this example, enter in the stations 0.0, 1500.0, and 3755.6840, with elevations of 2030, 2005, and 2040. Next, set the Vertical Curve for the middle station at 300.0.

The Slope Percentages and the Sight Distances are automatically computed for you. Select Save and Exit.

Step 6 (Quick Section):

Now we will create the cross section file (*.SCT). The cross sections define the existing ground for the road to tie into. Run Roads->Quick Section, fill the dialog as shown, and click OK. Your Offsets should be far enough away to tie in the Cut/Fill slopes.

Next, you will be prompted to load a centerline file or to to pick a polyline from the screen. Type C for Centerline and select the demo2.cl file we created earlier. Your section file is now created, your Command line should read as follows:

            Command: quicksct

            Pick starting point (CL-Centerline,P-Polyline): c

            Polyline should have been drawn in direction of increasing stations.
            Loading edges...
            Loaded 4244 points and 12207 edges
            Created 7964 triangles

            Writing section C:\Takeoff_2004\demo2a-og.sct

Step 7 (Design Template):

Let's design a wide boulevard with curb and gutter on the outside. The cut slope will be 2:1. In fill, the condition will be 3:1 in all fill under 6' and 2:1 in all fill over 6' in depth. Pavement depths will be 4" of asphalt.

First, select Design Template under Roads, name the .TPL file demo2, and open it. A dialog appears where you enter segments of the template. We will enter a symmetrical template, with 13.5' pavement sections on either side of the centerline, connecting to a 2' curb and gutter, with 18" of gutter and 6" of curb. Then we'll add a 6' shoulder.

For the lanes, click the Grades Icon.

The above 'child' dialog is shown, enter in: Slope: -2, Horizontal Distance: 13.5, and ID: EP. Click OK. You'll note that the lanes draw in the little preview window.

Click on the Curb Icon. Fill out as shown below and click OK.

Next up, we will add a shoulder, going up hill at 4% for 8'. Click on Grades again and enter in a slope of 4, a Horizontal Distance of 8, and the ID as SH.

We are now finished with the surface and can set subgrade. Select the Subgrade icon, second from the right (yellow color). We will create an asphalt subgrade which will run straight out and hit the curb.

Complete as shown and click OK. Here's what our template looks like so far:

Now we will add the outslope conditions. They are done with the Cut and Fill icons. Click on Fill and make three entries: under LEFT Slope enter in 3 (for 3:1), under Depth enter 6 (up to 6'), then again under LEFT Slope enter in 2 (for 2:1 over 6'). Select OK and click the icon for Cut. Just one entry here: under LEFT Slope enter in 2 (for 2:1 normal cut). Click OK.

Now click Save. The template is complete.

Step 8 (Process Road Design):

This is the routine that weaves everything together. Select Process Road Design, the last command in the Roads menu. The Specify Input Files column on the left allows you to choose the files to be used in the road design. We have already created the four needed files, go ahead and select them now and then click OK.

In the next dialog you can select different output features. For 3D viewing in the next step, toggle on Triangulate & Contour . It can be found in the bottom left portion of the Additional Earth Works Parameters dialog. Click OK.
Note: To generate a plot of road sections, specify an output section file in the 1st Road Design dialog. Then run Draw Sections in the Roads menu.

The following report listing the total Cut, Fill, Subgrade, and Curb volumes.

Trim existing contours inside disturbed area [Yes/<No>]? Press enter to say no

In the Contour Options dialog change the layer name to FINAL ROAD and make the contour interval 2. Click OK and your Road is complete! Here are the Road Design prompts:

Command: eworks

Initializing EarthWorks ...
Processing station: 3755.680
Drawing offset 3D polylines: TIE
Calculating volumes ...
Trim existing contours inside disturbed area [Yes/<No>]? <Enter>

Reading points... 2631
Inserted 2631 points
Inserted 2618 breakline segments

Drawing Triangulation 3D Faces ...
Contouring elevation 2040
Inserted 811 contour vertices.

Step 9 (3D Viewer):

Now that your Road is complete lets view it in 3D. Go to View, 3D Viewer Window, type in ALL, and press enter.

Here is our road with a Vertical Scale of 4. Color By Elevation has also been toggled on. Use the X, Y, and Z control bars at the bottom to rotate the drawing in the 3D viewer.