Creating a Railway Surface

You can design a railway surface by setting up track width, railway surface offset, sleeper length, left/right ballast shoulder width (fixed or as laws), rotation mode and cant (as laws). Unlike road design, there is no normal slope applied to the railway surface, the drainage being done through the ballast.

You can design a railway surface with transitions to attain superelevation in turns. The transition lengths as well as the superelevation value are functions of design speed, alignment geometry and standards. Key points/alignment points contain speed and minimum superelevation information (angle) used for design rules. The railway surface is based on a sweep, the angle and width of which are driven by rules/laws.

  1. From the Railway section of the action bar, click Horizontal Alignment .

    You switch into the Alignment Sketcher app. The Horizontal alignment initialization dialog box opens:
  2. Choose a profile (railway machines): Streetcar, Inter-city or High speed, because some parameters (design/maximum speed and curve gradient) may be different depending on the model selected.

    Profiles are based on the existing xml file of Data Setup called RailwayAlignmentDesign. The corresponding parameters and rules are displayed in the lower part of the window. They correspond to the selected profiles, managed in Data Setup. You cannot edit them.

    Profiles are managed in Data Setup. It is compulsory to select a profile to validate the surface creation. Without selection, the OK button is disabled.

  3. Click OK.
  4. Choose key parameters and rules that should apply to the future railway alignment.
  5. To create your profile with points, lines and arcs, click Alignment Profile .
  6. To change the superelevation value, double-click an horizontal alignment in the tree.
  7. Double-click a key point.
  8. To edit the superelevation rate, do either of the following:
    • Under the Parameters section, use the combo box of Superelevation to edit the rate of the maximum slope in the following road turns (5% for example). The slope angle on the selected alignment point is not modified, next alignment points inherit from the current rate and the Superelevation field is renamed into Current superelevation containing the inherited rate.

      To modify the superelevation value again, click Edit next to Current Superelevation.

    • Under the Design Rules section, use the combo boxes to edit the superelevation tables/laws (defined in Design Rules in Data Setup) used to connect transition sections with different superelevation rates.

      When no superelevation value has been set, the current value displays the information of the previous alignment points.

      Design Rules can be selected in session. They allow to define several horizontal radius tables depending on a superelevation rate. For example, you can add curve radius rules according to the speed.

  9. To create a vertical alignment, click from the Alignment assistant.
  10. To create a 3D alignment, click from the Alignment assistant.
  11. To display alignment segment information, click from the Railway section of the action bar and select an alignment point.
    An Alignment segment information window appears. You can read information about the start/end point position, elevation, start direction and segment length.
  12. Export alignment information in a report to the format of your choice by clicking Export Alignment Report from the Railway section of the action bar.
  13. To create a railway surface, select a 3D Alignment in the tree or in the 3D area.
  14. From the Railway section of the action bar, click Railway Surface .

 

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