Frequency to Apply Assemblies Dialog Box

Use this dialog box to add chainages to a corridor.

You can specify the frequency and placement settings for stations along the corridor.

Note: You can change the default values for the frequency and placement settings from the Edit Feature Settings dialog box for the CreateCorridor and CreateSimpleCorridor commands.

The properties table displays the following settings:

Corridor Information

Displays general information about the corridor.

Corridor Name

Displays the corridor name.

Baseline Name

Displays the corridor baseline (alignment) name.

Start Station

Displays the value for the first chainage for the current assembly region.

End Station

Displays the value for the last chainage for the current assembly region.

Horizontal Baseline

Along Tangents

Specifies the assembly insertion frequency along the straight portion of a horizontal baseline. Enter a value or click and select a distance in the drawing.

Along Curves
Specifies how the frequency for inserting assemblies along curves is determined.
  • By Curvature: Horizontal baseline curves are tessellated using the Mid-Ordinate Distance to Define Curvature value. Stations are created along the tessellated curve at each point where the tessellation touches the curve, as shown in the following illustration:

  • At an Increment: Stations are placed along the curve at the value specified in the Curve Increment field.
  • Both: Uses both the By Curvature option and the At an Increment option.
Curve Increment

Specifies the assembly insertion frequency along the curve portion of a horizontal baseline. Enter a value or click and select a distance in the drawing. This field is not editable if By Curvature is selected as the Along Curves setting.

Mid-Ordinate Distance to Define Curvature
Specifies the value to define the mid-ordinate distance by which to tessellate horizontal baseline curves. This field is not editable if At an Increment is selected as the Along Curves setting.
Along Spirals

Specifies the assembly insertion frequency along the transition portion of an alignment. Enter a value or click and select a distance in the drawing.

Note: This setting is not used when a feature line is specified for the horizontal baseline.
At Horizontal Geometry Points

Specifies whether the assembly should be inserted at horizontal baseline geometry points where the horizontal baseline geometry changes (such as the start of a curve).

At Superelevation Critical Points

Specifies whether the assembly should be inserted at superelevation critical points (such as ‘end normal crossfall’, ‘level crossfall’, ‘reverse crossfall’ and ‘begin full super’).

Note: This setting is not used when a feature line is specified for the horizontal baseline.

Vertical Baseline

Along Vertical Curves

Specifies the assembly insertion frequency along curve portions of the profile geometry. Enter a value or click and select a distance in the drawing.

Note: This setting is not used when a feature line is specified for the vertical baseline.
At Vertical Geometry Points

Specifies whether the assembly should be inserted at vertical baseline geometry points where the vertical baseline geometry changes.

At High/Low Points

Specifies whether the assembly should be inserted at the high and low points of the vertical baseline geometry.

Offset Target

At Offset Target Geometry Points

Specifies whether or not to automatically add assemblies based on offset target objects (feature lines, alignments or polylines).

Note: If both an assembly frequency setting that references horizontal geometry and a setting that references vertical geometry apply to a portion of a corridor, the setting that results in a smaller interval is used. For example, if a segment is both a horizontal straight and a vertical curve, and the vertical curve frequency adds assemblies at more frequent intervals, the frequency specified for vertical curves is used.
Adjacent to Offset Target Start/End
Specifies whether the assembly should be inserted adjacent to the offset target start and end. This setting creates stations at a small distance before the offset target start and after the offset target end, rather than creating the stations exactly at the offset target start and end. For more information, see About Changing the Frequency of Stations in a Corridor Region.
Along Offset Target Curves
Specifies how the frequency for inserting assemblies along offset target curves is determined.
  • By Curvature: Offset target curves are tessellated using the Mid-Ordinate Distance to Define Curvature value. chainages are created along the tessellated curve at each point where the tessellation touches the curve.
  • At an Increment: Stations are placed along the curve at the value specified in the Curve Increment field.
Curve Increment

Specifies the assembly insertion frequency along the curve portion of an offset target. Enter a value or click and select a distance in the drawing. This field is not editable if By Curvature is selected as the Along Offset Target Curves setting.

Mid-Ordinate Distance to Define Curvature
Specifies the value to define the mid-ordinate distance by which to tessellate offset target curves. This field is not editable if At an Increment is selected as the Along Offset Target Curves setting.

Options for Adding and Deleting Stations

Adds a chainage. You are prompted to select a chainage location in the drawing. The chainage is added to the table of chainages.

Deletes the chainage selected in the table of chainages.

Note: Stations added by the Corridor Transition Panorama vista cannot be deleted from this list.

Stations Table

The chainages table displays the following columns:

Station

Displays the chainage value on the baseline.

Description

Specifies a description for the chainage. Click to enter a description.