HOME  CDS Tutorial Manual
Forming a platform for bulk earthworks

In this Tutorial you will learn
• To locate a Design Platform horizontally within a model.
• To set the platform at a desired design height.
• To apply batter slopes from the edge of the platform to the model.
• To calculate the volume on material to be moved to construct the platform.
• To adjust the design height of the platform to balance the earthworks.

Base data has been supplied in a Job with an ID of "PAD" Start CDS and use File Open to open "pad.cdsdat" located in the my documents\foresoft\cds4 tutor folder. The screen should appear as seen below.

 Pull down the Contour menu, and use Surface Parameters to make sure the Natural Surface is current.Next form the model and contour the surface which should appear  as below. The client requires us to position a level pad with dimensions 180 metres by 100 metres to use for standing a dragline, and the earthworks should be close to balanced with a small excess of cut being preferable.
 In this instance we have examined an existing contour plan of the site, and in the time honoured method of design we have pencilled in a rough area where we would like to place a pad, and scaled off one of the corners.The bottom left hand corner of the pad should have coordinates of East 8690 and North 7540 and the long side of the pad is on a bearing of 330 degrees.

Pull down the Points menu and select Add Points - you will notice that your cursor changes to a cross.
Position it somewhere on the model and select a point.
When the Add/Edit/Query box appears, enter a Point Number of 500, and Easting of 8690, Northing of 7540 and a Design Height of 225.
Select OK, and Point 500 will appear on the screen.
Now pull down the Points menu and turn Add Points Off (or press the Escape key to achieve the same ‘off switch’) and the cursor will revert to the normal pointing arrow. Next pull down the Cogo menu and select Calculate by Bearing and Distance to see the screen below right
 Enter 500 as the point to start from followed by 330 for the bearing and 180 for the distance. Select Apply and you will see point 501 appear.To get the next point, position the cursor in the “bearing” field and press the ‘R’ key to add 90 degrees to the current bearing.  Tab to the Distance filed and enter 100, then select Apply to create Point 502.   Again move to the bearing field, press ‘R’ and then enter the distance of 180 and Apply to create point 503, which is the final corner of our pad.

I suggest that you define pads in a String Folder with a name of "PAD". This way we logically group the pads together; gthough it is not necessary.
Drag the Strings box down to the bottom right hand corner so it is clear of the area where the pad is located
Type in ‘pad’ for the folder name.
Note that it doesn’t matter whether you try and use upper case or lower case, the program will convert everything to lower case as you enter the Folder name. This is necessary to avoid some slight confusion between file or folder naming conventions in different version of Windows. Use an ID of P1 and accept the default pen and linetype.
Move the cursor into the string entry field, and either type in the string 500,501,502,503,500, or use your mouse to select the points.

 We now need to tell Ezigrade that this is a pad. In previous versions wer assumed everything in the pad folder was a pad. We now explicitely tell the software that we have a pad. Left click on the pad string and it is selected. Now click on the Platform -> Add Pad menu item.   Now click escape. We now need to set the pad parameters. Click on Platform -> Parameters

CDS will now show us the Platform design as we go. We can change parameters and see the result straight away. The first thing I suggest is to guess an initial start height. I have added a value in of 225 and click OK. At the end of the process your screen should be similar to the one shown above.

The idea is to iteratively change the values and look on the screen at how it looks. The pad knows how to display itself and nothing is added to the database yet.

 Please also be aware that you can use a road template or templates to define nearly anything you wish. Just be aware that with a platform the height of the pad is constant and the pad is a closed structure.   Often we wish to balance the cut and fill. Simply click the "balance volume" button and the appropriate height is calculated. In this case it is  223.370 At present there is no option for compaction / expansion of fill.

Once you are happy with the design then click on Platform -> Merge. A new triangular surface is created. You should turn off the platform display. Look under the View menu and you can see the "Platforms" icon. If you change to the new surface you can display contours, height displays etc.

 If you want to subsequently change the pad design then click on Platform -> Unmerge; then change parameters as appropriate. Then redo the Platform -> Merge.

If you have multiple platforms then the procedure is the same. You can click within the pad to select or go into the Platform -> Parameters and change to the appropriate pad. Make sure you give them unique names so everyone knows which platform you are referring to.

So we have a natural surface and the appropriate design surface for the pad. We can do a formal volume between 3 surfaces. We can export the job to Ezigrade if you want to grade the pad with Trimble, Topcon, Agguide etc. Or export as an XML for many civil grading solutions. You can even stake out the design for a more manual solution.