Create Surface Roads

Generating surface roads on a reference topography

Create Surface Roads

To access this dialog:

  • Run the command create-surface-roads

  • Use the quick key combination 'csr'

Getting Started

The Create Surface Roads dialog is used to create roads on a reference topography, using a centreline and various parameters describing road profile and cut and fill batters.

General Workflow

After running the command, the Create Surface Roads dialog is displayed in a dockable control bar.

The general workflow for creating a surface road is:

  1. Define initial road settings: select a loaded topography wireframe and
  2. Copy or create a road reference line; you can either digitize a new line or use any loaded string object. Lines can represent the center line, left edge or right edge.
  3. Edit road properties, such as vertical and horizontal gradient adjustments.
  4. Generate road information, such as cross-sections, outlines or wireframe surface. These settings will determine the profile of your road as it traverses the topography, including deviations from the topography elevation values.
  5. Generate the batters needed to support the road in the topography. These batter surfaces and volumes are used to calculate independent cut and fill volumes.
  6. Update the topography to include the new road and batters.
  7. Save surface road data to the database.

Where information is missing from previous steps, a button will be disabled and information posted alongside indicating missing information.

Any subsequent edits to earlier steps, for example, editing the centerline after road batters have been generated, will remove existing data for later steps. Loaded data objects will remain, but may be emptied if they no longer contain valid information.

Steps may also be run automatically on completion of the previous step, by ensuring the Auto apply option has been selected.

In the case of Generate Road, Auto apply will occur after any change in the reference centerline.  

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It is recommended that steps are run individually first, to determine whether the processing time is suitable for automatically applying for all stages.


Saving Surface Road Data

By default, surface road data will be saved to your database but you can also specify another folder (which will be created if it doesn't exist).

Clicking Save will transfer all generated surface road data to your selected location and leave the Create Surface Roads task open, alternatively you can Save & Close or simply Close if you don't wish to save your changes.

 

Initial Road Data Configuration

  1. Any loaded wireframe can be used as the topography by selecting it in the Topography drop-down list. It is assumed this will be a valid DTM; no additional validation is performed. The default selection will be the current wireframe object.
  2. Next, define a Road Name. Each unique road name will eventually be associated with a range of data objects that represent the aspects of the surface road, including all outline, surface and solids data.
  3. Decide on a Road Width.
  4. Review the initial Cut and Fill Volumes.

    These values provide an initial check on the volume of material to be moved or extracted. You can see both Cut, Fill and Excess volumes.

    For example, the road excavation below (showing an updated topography from later in the process) results in predominantly cut operations, will a small fill to shore up the lower left road end:


    In this case, the Cut volume is significantly higher than the Fill volume, leaving a sizeable Excess volume.
  5. The next step is to digitize or select a reference line - this is explained in more detail in the section below.

If you've already created a road and enter a new Road Name, you will be asked if you want to copy the settings from the previous road. This is a good option if you're experimenting with road layout variations. If previous road data is unsaved, you'll get the chance to save it before copying.

 


The Surface Roads Toolbar

Along the top of the panel there is a command toolbar containing access to road generation and topography update commands.

More about the Create Surface Roads toolbar...



Reference Line Adjustment

Road centerline data can be adjusted either using a horizontal or vertical adjustment of string vertices. The type of editing is determined by expanding either the Reference Line Horizontal Adjustment or Reference Line Vertical Adjustment command groups.

More about surface road reference line adjustment...


Gradient Reporting

Road gradient constraints let you ensure your generated road geometry is practical for your fleet.

More about surface road gradient reporting...


Cut & Fill Volumes

Cut and fill volumes are calculated throughout road generation.

More about surface road cut and fill volumes...



Road Sections and Parameters

The Road Parameters group and associated Generate Road button are used to calculate the road surface from the reference line. This will either be a simple fixed-width road along the full length of the reference line, using the same cross-sectional shape at each point, or a more complex arrangement where road reference line shapes can potentially vary at any point along the line.

More about surface road sections and parameters...

 

Designing Road Batters

Batters connect the road surface to the surrounding topography. Fill batters will usually have different structural requirements to cut batters, so there are two different but functionally identical control groups for defining them. Benches may come in two forms: parallel and horizontal.

More about surface road batter design...


Update the Topography

Once the road and batters look as desired, the “Update Topo” button can be used to create a copy of the original topography.

More about updating the topography...