Low Volume Road Design using Softree’s RoadEng ™

  Starting Out
  Edit Ground
  Edit Templates
  Labels & Scales








  Go to Design


This Appendix to the UW Forest Engineering Handbook is meant as a brief guide on basic low-volume road design using Softree’s road design package, Roadeng. The ultimate aim is to help a person to start designing their roads quickly without having to go through all the ins and outs of the program. It will also be assumed that the user has already input the traverse, be it by hand or through a data collector.


Starting Out

So you have a traverse entered into RoadEng’s Survey Module and saved as a .db1 file. You’re ready to begin work in the Location Module. On the Survey/Map window, click on the module menu and select "To Location Design." The Location Module should open up.

Under the File menu, select "New." You will be asked to select a P-line traverse to use for the design. Go to the directory where you saved the traverse, and select the file that you want to use. Click "OK" and the traverse opens up.

Now is the time to make some choices. If you have not used the program before or have not set it up, you’ll need to set certain parameters before getting too far ahead in design work. Think of it this way: by spending a little bit of time adjusting things now, you can save a lot of time later.

The exact order that you set your preferences is not critical. By the time everything is set, you can save it as a design layout and so will be available any time.


Edit Ground

This feature allows you to edit the different ground layers within the survey. It’s probably the first thing that you want to make sure is set. For most cases in forest road construction, using overburden is sufficient. However, there are times when it may be necessary to use rock, or hardpan, etc. as the case may warrant.

You can also set the cut and fill slopes, which in many cases is 1:1 for cut slopes and 1½:1 for fill slopes. As well, set the cut and fill expansion factors to their appropriate values. If one were to say that excavated material expanded by about 25%, then the expansion factor would be 1.25. Likewise, if the fill material was expected to compact by 20%, then the expansion factor would be 0.8. This may be repeated for any current or new ground type that you wish. Where the ground types become useful is when you assign them to your road design.


Edit Templates

Under the Edit menu, select "Edit Templates." The new window allows you to create new templates, edit existing templates, and delete templates.

To create a new template, type in a four character descriptive code and then a suitable name, then click on add. Then you can begin editing different aspects of the template.

The "Road" fields will allow you to adjust the road template used in the cross-section. Initially set the road width, which is the subgrade and not the driving surface. By clicking the "plus-sign,", you can change the slope of the roadbed to get inslope, outslope, crown, or flat. A typical grade for the road cross section is either 3% or 4% for inslope, outslope, and crown.

The ditch settings can be somewhat confusing. The width in RoadEng is measured across the bottom, not the top. So if you want a typical ditch that is 3 feet wide at the top and one foot deep, just specify zero for width and 1 for depth. Clicking on the "plus-sign" pops up another window. Keep the left and right slopes on autocalc, and set the ditch slope to 67% (for 1½:1).

For the Left and Right Final Slopes categories in the editor, set both cut and fill slopes to auto. RoadEng will automatically use those values you set for the cut and fill slopes in the ground type editor.

When you’re satisfied with the settings, click ok to return to the editor. When you’ve got all the templates that you need, click on ok.

Some templates that you’ll probably want to keep around:

Keep in mind too that a rough design is helpful to get an idea of what template needs to go where, so start with a basic crown or outslope template and go from there.


Labels and Scales

Each window (Profile, Plan, X-section, and Data) has its own set of display options. It’s helpful to start each design session with a consistent view, especially with the scale of the plan and profile. Other items, such as labels, grids, and the like are better when consistent as well.


To set the profile scale, as well as other features of the profile window, open up "profile options" under the view menu.

For the profile, a scale of 1:120 vertical and 1:1200 horizontal is useful. You can, however, use a scale of 1:1, such as 1:120 for both vertical and horizontal. This helps out when doing a lot of cutting or filling, which may look like you’re carving out the hillside on a distorted scale, but isn’t so bad on a 1:1 scale. Experiment and find a scale that gives enough detail to see the road far enough ahead so you can easily design.

For labels, less is usually better. Stick with what you need most: grade, BC/EC, curve K values, and floating labels. The index labels or L-station can be helpful at times.

For sub-windows, cut/fill and mass haul are sufficient for starting out.

Other features to include are P-line topo (shows the original profile of the survey), culverts, grid (helpful for plotting out and then doing a manual design, scroll bars, and tick marks.

Plan View

For the plan view, a scale of 1:360 or 1:480 seems to give enough detail. Like with the profile, find a scale that includes enough detail, and shows enough of the road to design ahead. As well, a scale, in any case, should be one that matches a standard engineering ruler so that you can scale things off from a printout or plot.

To set the scale, open the "plan options" under the view menu. Input the desired scale, and pick what features to display. Generally, the more useful features for getting started are the scroll bars, north arrow, tick marks, culverts, road edges, and labels.

There are several labels to choose from. What are definitely needed are the BC/EC labels, curve radius labels, and floating labels. At times the index labels are necessary, just to keep track of where you’re at.

Section View

A scale of 1:120 is fine for on screen design. For printing out on letter size paper, a scale of 1:60 works well.

With the section window, you can add in several fields under the section for additional information at each reporting point. These can be selected from the "section options" under the view menu. Pick the fields you want by clicking on the "fields" button and then selecting from the list of available fields.

For design work, the generally more useful fields are L-station, grade next, grade last, side slope left, side slope right, cut area, fill area (these two are for balancing), and horizontal offset. Keep in mind that different fields have their place, but also that you don’t want too much clutter in your window. Just keep what is relevant.

Also for the section options, select grid, road prism, topography, culverts, display section, layers, stripping, and both vertical and horizontal alignment. The last two allow you to move the section with the mouse in the section window to balance the design.


For the Data window, you need to select different fields of information to display. You can have it set up one way to view while designing, and another way to take with you into the field to do offsets for the L-stations.

To select the fields, while the data window is active, select "data options" under the view menu. Pick out the fields by clicking the "columns" button.

Some common and useful fields are L-station, cut depth, horizontal offset, grade, horizontal distance, and slope stake left and right.

The data options window also asks which points to use for reporting points. Go with survey stations, but also include the BC/EC points for both plan and profile. This helps in finding the P-station to enter into the assign templates window for the beginning and end of curves, turnouts, and fill widening. When it comes time to print out the data sheets, just uncheck the curve points.


That’s a lot of work to just start off, and you haven’t even started the design. But taking the time now to get the windows set up pays off, since you can save the whole thing as a layout template. Just select "save screen layout" under the file menu, and then give it a descriptive file name. You can recall this at any time with this and other designs.

Now, onto Design.


Tuesday, January 15, 2002