Alignment Layout Parameters Window

Use this window to display and edit many attributes of any given single sub-entity within an alignment.

You can use the Alignment Layout Parameters window to change individual lines, curves, and spirals in the alignment. Use this window along with the Alignment Entities vista, which displays all of the sub-entities that make up a given alignment.

You can edit available parameters. You cannot edit parameters that are unavailable (shaded).

If the alignment uses design criteria, then the Alignment Layout Parameters window contains up to three panels that can be collapsed by clicking . If design criteria has not been associated with the alignment, then only the Layout Parameters panel is available.

You cannot dock the Alignment Layout Parameters window, but you can pin or resize it.

This window stays open when you grip edit the alignment or enter another command. The window closes when you either delete the currently selected alignment, click the X button in the upper right-hand corner of the window, or click on the Alignment Layout Tools toolbar.

Design Speed

Specifies the design speed of the current sub-entity.

Note: If multiple speeds are assigned to a sub-entity, then the highest speed is used to look up constraint values from the design criteria file and to validate the design checks. This ensures the safest design for that sub-entity.

Design Criteria Panel

The following parameters are displayed only if design criteria has been associated with the alignment.

Use the Design Criteria panel to apply design criteria that is different from the default values that have been set for the alignment. To change a criterion value, click the Value cell in the appropriate row.

A warning symbol in the Property column indicates that the sub-entity design violates the criteria set in the design criteria file. You can find and correct the specific parameter that has been violated by examining the Layout Parameters panel.

Minimum Radius Table

Defines the minimum radii for a given road type and design speed.

Transition Length Table

A table of values in the Superelevation Attainment Method formulas. You can use the table to calculate the distances between the critical superelevation transition points for different types of roadways as a function of curve radius and design speed.

Attainment Method

Specifies how superelevation is applied, and the method (crowned or planar) that is used to calculate superelevation transition stations for different types of roadways.

Layout Parameters

Use this panel to examine and change the general layout parameters of the selected sub-entity.

Click Show More to expand the number of parameters that appears in the window. The default, collapsed view displays editable and other important parameters. Use the horizontal and vertical scroll bars when the list is longer or wider than the window.

When a design criteria file has been associated with an alignment, the Constraints column displays the value to which a given parameter is limited. The selected design criteria file defines the constrained values. When a parameter value violates the range displayed in the Constraints column, a warning symbol appears next to the parameter name.

Note: The constraint definition for each alignment entity determines the parameters that are displayed in the Layout Parameters panel.

Line

Entity

Specifies a number for the Line, in the order of creation.

Curve Group Index

Specifies the curve group description.

Curve Group Sub-Entity Index

Specifies the curve group sub-entity description.

Type

Specifies either Line, Curve, or Spiral as the sub-entity type.

Tangency Constraint

Specifies how the entity is constrained by other entities: either Not Constrained (Fixed), Constrained By Previous (Floating), Constrained By Next (Floating), or Constrained On Both Sides (Free).

Parameter Constraint Lock

Specifies whether the parameters associated with the Parameter Constraint property may be edited.

  • (Locked): Only the parameters permitted by the Parameter Constraint property are enabled for editing.
  • (Unlocked): All parameters (with some exceptions) are enabled for editing.
Parameter Constraint

Specifies the number of points in the constraint of the tangent.

Length

Specifies the Line length.

Note: You can edit the length of a floating line that is attached to the end of an entity.
Bearing

Specifies the direction of the line.

Start Station

Specifies the starting station of the line for the solved portions of the alignment.

End Station

Specifies the end station of the Line for the solved portions of the alignment.

Start Point

Specifies the XY coordinates for the start point of the Line.

End Point

Specifies the XY coordinates for the endpoint of the Line.

Pass Through Point1

Specifies the XY coordinates of the first user-specified pass-through point.

Pass Through Point2

Specifies the XY coordinates of the second user-specified pass-through point.

Curve (independent or in SCS)

Entity

Specifies the curve number relative to the order of creation.

Curve Group Index

Specifies the curve group description.

Curve Group Sub-Entity Index

Specifies the curve group sub-entity description.

Type

Specifies Curve as the entity type.

Radius

Specifies the radius of the curve entity.

Degree of Curvature

Specifies the degree of curvature that was calculated for the curve. This value is directly related to the Radius value. It uses the same constraints, and if one changes, the other updates automatically.

Length

Specifies the length of the curve entity.

Pass Through Point1

Specifies the XY coordinates of the first user-specified pass-through point.

Pass Through Point2

Specifies the XY coordinates of the second user-specified pass-through point.

Pass Through Point3

Specifies the XY coordinates of the third user-specified pass-through point.

Center Point

Specifies the XY coordinates of the center point.

Start Station

Specifies the starting station of the curve for the solved portion of the alignment. Unsolved curves do not display a Start Station.

Start Point

Specifies the XY coordinates of the start point of the curve.

End Station

Specifies the end station of the curve for solved portions of the alignment. Unsolved curves do not display an end station.

End Point

Specifies the XY coordinates of the endpoint of the curve.

Direction At Through Point 1

Specifies the XY coordinates of the first user-specified pass-through point.

Direction At Through Point 2

Specifies the XY coordinates of the second user-specified pass-through point.

Greater Than 180 Degrees
  • Displays True if the curve angle is defined as greater than 180 degrees.
  • Displays False if the curve angle is defined as less than 180 degrees.
Compound
  • Displays True if the curve is defined as compound to the curve before it.
  • Displays False if the curve is defined in the reverse direction to the curve before it.
Delta Angle

Specifies the included angle of the solved portion of the curve.

External Tangent

Specifies the distance from either the beginning of the curve (PC) to the point of intersection (PI), or from the PI to the end of the curve (PT).

Chord Direction

Specifies the bearing along the line joining the beginning of the curve (PC) and the end of the curve (PT).

External Secant

Specifies the radial difference from the PI to the midpoint of the curve.

PI Included Angle

Specifies the included angle between the incoming and outgoing tangents of the curve.

Chord Length

Specifies the distance along the line joining the beginning of the curve (PC) and the end of the curve (PT).

Mid-Ordinate

Specifies the distance from the midpoint of the curve, perpendicular to the midpoint of the chord.

PI Station

Specifies the station value of the PI by adding the PC to the PI tangent length to the station value at the beginning of the curve (PC).

Spiral

Entity

Specifies the spiral number relative to the order of creation.

Curve Group Index

Specifies the curve group description.

Curve Group Sub-Entity Index

Specifies the curve group sub-entity description.

Type

Specifies Spiral as the entity type.

Constraint1

Specifies the spiral as either Fixed or Free.

Constraint2
  • Specifies the Spiral In, Radius, and Spiral Out for free spirals that are part of a Spiral-Curve-Spiral group.
  • Specifies the start point, direction, radius, and length for fixed spirals.
Spiral Type

Displays True when the spiral has a curve at both ends.

Start Station

Specifies the Start Station at the beginning of the spiral.

Start Point

Specifies the XY coordinates of the Start Point of the spiral.

End Station

Specifies the end station for the solved spiral portions of the alignment. Unsolved portions do not display an end station.

End Point

Specifies the XY coordinates of the End Point of the spiral.

Incurve

Specifies the incoming curve radius.

Length

Specifies the length of the Spiral.

A

Specifies the A value.

Compound
  • Displays True if the curve is defined as compound to the curve before it.
  • Displays False if the curve is defined in the reverse direction to the curve before it.
Radius In

Specifies the incoming curve radius.

Radius Out

Specifies the outgoing curve radius.

Total X

Specifies the tangent distance between the beginning point of the incoming spiral (TS) and the endpoint of the spiral and beginning point of the circular curve.

Total Y

Specifies the perpendicular offset distance between the beginning point of the circular curve (SC) and the incoming tangent.

Short Tangent

Specifies the distance from the spiral point of the horizontal tangent intersection (SPI) to the end of the spiral (SPI).

Long Tangent

Specifies the distance from the beginning of the spiral (TS) to the spiral point of horizontal tangent intersection (SPI).

P

Specifies the offset distance from the incoming tangent to the beginning point (PC) of the shifted circular curve.

K

Specifies the abscissa between the beginning point of the spiral (TS) and the beginning point of the shifted circular curve.

Spiral Definition

This read-only field specifies the spiral definition. If the alignment is created using the Alignment Layout tools, or converted from AutoCAD entities, then the spiral definition for these spirals is specified as one of the following values: Clothoid, Bloss, Cubic (JP), Cubic Parabola, Sinusoidal, Sine Half-Wavelength, Bi-Quadratic.

If the alignment is created using a dynamic offset alignment command, the spirals have a special geometry based on the parent alignment spiral definition with the offset parameter. So, for dynamic offset alignments, the spiral definition can be specified as one of the following values: Offset Clothoid, Offset Bloss, Offset Cubic (JP), Offset Cubic Parabola, Offset Sinusoidal, Offset Sine Half-Wavelength, Offset Bi-Quadratic.

PI Included Angle

Specifies the included angle between the incoming and outgoing tangents of the curve.

SPI Station

Specifies the station value of the SPI. Adds the tangential distance from the beginning of the Spiral (TS) to the SPI to the station value of the TS.

SPI Northing

Specifies the XY coordinates of the spiral point of horizontal tangent intersection.

SPI Easting

Specifies the XY coordinates of the spiral point of horizontal tangent intersection.

SPI Included Angle

Specifies the angle representing the difference in direction of the incoming tangent and the outgoing tangent of the spiral.

Radial Point Northing

Specifies the coordinates of the spiral northing.

Radial Point Easting

Specifies the coordinates of the spiral easting.

Design Checks

The Design Checks panel displays the name and contents of the design check set that is associated with the alignment.

When the sub-entity design violates a design check, a warning symbol appears next to the affected design check.

Note: The Design Checks panel is available only for alignments that use a design check set.