About Vertical Alignment

This topic provides you with more information about vertical alignment.

This page discusses:

Alignment Section

This section provides you with more information about the commands available in the Alignment section of the action bar.

In the Alignment sketcher app for vertical alignment design, three commands are available in the Alignment section of the action bar:

  • a transition using Transition . For more information, see Creating a Transition.
  • a line using Line
  • a circle using Circle

When clicking Line or Circle, the following parameters are available in Tools Palette:

  • Start point: start point of the curve created using the sketcher assistant.
  • Start gradient: gradient of the tangent of the curve at the start point. It is provided as a ratio measure [-100%;+100%] equivalent [-45deg; +45deg].
  • Horizontal length: length measured as distance along the horizontal alignment of the curve.
  • Radius (for arc and parabola only):
    • For an arc: circle radius
    • For a parabola: the true radius of a parabola at its vertical axis (the zero-gradient point of the parabola). The minimum radius is twice the focal length of the parabola (the distance between the focal point and the vertex).
  • Convex/Concave (for arc and parabola only): Orientation of the arc, convex (Boolean="true"). The minimum radius is the distance between the vertex and the center point along the positive direction of the vertical axis. Concave (Boolean="false") means: along the negative direction of the vertical axis.
  • You can create vertical alignment points and enter them to adapt to the terrain topography and differentiate these points for each construction type (bridge, dam, ground, tunnel).

Alignment Dialog Box

This section describes some features of the Alignment dialog box.

Bounding Box

The Bounding box width option lets you refine the display of objects you want to transfer in the vertical sketch.

By default, the Bounding box width option is selected and its default value is equal to the right of way value of the horizontal alignment. To change this value, click and enter a new value, or modify the value of the right of way.

The import behavior is different whether the object is an exact or a polyhedral geometry. Exact geometry must be first imported and then refined, whereas polyhedral geometry is refined and then imported.

Visualization Modes

Multiple visualization modes are available.

For exact geometry, the compatible visualization modes are the following:

Geometry/Visualization Mode Projection Intersection Silhouette
Point
Wire
Surface
Volume

For polyhedral geometry, the compatible visualization modes are the following:

Geometry/Visualization Mode Projection Intersection Silhouette
Point
Wire
Surface
Volume

Vertical Curve Navigation

You can navigate through the curves, following the trajectory of the alignment. The alignment must contain a curve, spirals, and tangents.

When the horizontal alignment has the following configuration Tangent-Spiral-Circle-Spiral-Spiral-Circle-Spiral-Tangent (compound transition with reverse arcs separated by two spirals), you can visualize the vertical line representing the co-tangent point and displaying the Spiral-Spiral string.

When you double-click a tangent, a PI, a spiral, or a curve, the Vertical Curve dialog box appears, and navigation arrows are available. When you click an arrow, the display automatically switches on the previous or next curve, and places the current curve with its tangents and spirals at the center of the 3D area. The dialog box updates with the next curve information.

Each curve is modified independently from the others. No need to validate and to close the dialog box after each curve editing. If you click Cancel, the modifications made on all the curves are canceled.