Use this dialog box to specify details for adding a slip lane (or bypass lane) to a roundabout.
In some roundabouts, a slip lane can be added between an approach road and a departure road to reduce the traffic moving through the circular area of the roundabout.
Slip Lane Parameters
These parameters specify the geometry of an optional slip lane that can be added to a roundabout.
To see a conceptual illustration of the parameter location, place your cursor in the entry field for the parameter. The conceptual illustration is displayed in the dialog box.
- Segmentation Line Length
-
To achieve the correct geometry in approaches with base alignments that are not straight, the deceleration lane and taper are segmented. The default value of the segment length is 1 unit. Note that lower values will improve accuracy, however reduce the speed of operation.
- Lane Width
-
Specifies the width of the slip lane.
- Length of Deceleration Lane
-
Specifies the length of first part of the slip lane where the vehicle will decelerate and bear onto the right or left turning lane.
- Radius
-
Specifies the radius of arc in the middle of the slip lane.
- Length of Acceleration Lane
-
Specifies the length of the road where a vehicle will accelerate to merge into a main road.
- Taper Length
-
Specifies the length of the road where a vehicle will merge into a main road.
Draw Pavement Markings
Specifies pavement marking for slip lane components. You can specify a linetype, width, and an offset. If you do not want pavement markings, clear the check mark from the Draw check box.
- Outer Edge
-
Specifies the pavement markings for the outer edge of the slip lane.
- Decelerating Transition Line
-
Specifies the pavement markings for the decelerating transition line of the slip lane.
- Accelerating Transition Line
-
Specifies the pavement markings for the accelerating transition line of the slip lane.
- Draw
-
Specifies whether or not to add (draw) the pavement markings.
- Linetype
-
Specifies the linetype of the pavement markings.
- Width
-
Specifies the width of the pavement markings.
- Offset
-
Specifies an offset for the pavement markings.
Alignment Style
Specifies the alignment style from the list of styles available in the drawing.
Alignment Layer
Specifies the alignment layer from the list of layers available in the drawing.
Alignment Label Set
Specifies the alignment label set from the list of label sets available in the drawing.
Alignment Name Prefix
Displays the name of the alignment used to specify the central approach road. This name is used as a prefix for the alignments that are generated by the roundabout creation. For the right edge alignment, the suffix “_EDGE_RIGHT” will be added to the alignment name. For the left edge alignment, the suffix “_EDGE_LEFT” will be added to this name.