Deflecting Island

Use this function to design deflecting islands along any selected reference line.

• The resulted Deflecting Islands will be a 2D drawing.

• The function does not modify the road model or the Quadri database.

Run the function from the following location:

MOUS_ICO Menu: Road > Intersection Tools > Deflecting Islands

The dialog Deflecting Islands will pop up.

• The dialog has two tabs: Island and Kerbstone.

• The parameters in grey cells cannot be edited, these values are read/calculated by the function.

  • E.g., the angle is read when the primary and secondary lines are selected, the parameters, r1 and r2, are calculated depending on the values b1 and b2, which are to be defined by designers.

• Use the button Help Parameters to see the graphical representation of the parameters.

• The unit of linear measurement and angular measurement is meters and decimal degrees, respectively.

Create

Use this button to select the reference lines (primary and secondary). Deflecting island will be designed and drawn to a secondary line. The parameters can be defined before selecting the reference lines or after selecting the reference lines.

Command prompts for:

Select secondary road centerline, Deflection Island's location (bottom point):

Pick centerline primary road, left arm of intersection as seen from the deflection island:

A preview of the deflecting island will be drawn in CAD.

• The preview will be updated instantaneously when the values are modified in the dialog.

• To edit the parameters, type in the value and press Enter or select another cell in the dialog.

Edit

Use this function to edit previously designed deflecting islands. To edit, select the island line not the curbstone line.

b1 <

Use this button to select the distance from the top right rounding radius to the edge line.

• Select the top point on the main road and a temporary curve is shown in the drawing.

• Move the cursor across the main line to define the distance on the right turn.

• Alternatively, the value for distance can be typed in the dialog at the field b1.

b2 <

Use this button to select the distance from the top left rounding radius to the edge line.

• Select the top point on the main road and a temporary curve is shown in the drawing.

• Move the cursor across the main line to define the distance on the left turn.

• Alternatively, the value for distance can be typed in the dialog at the field b2.

Bottom <

Use this button to select the bottom point of the deflecting island.

• Click the button and the end of the deflection island is dragged along the secondary line as the cursor is moved.

• Pick the bottom point.

• The length of the deflecting island will be updated in the dialog as the bottom point is changed.

• Alternatively, the length of the deflecting island can be defined in the dialog at the field hb.

Island

• A = Angle

• r1 = Right rounding radius

• r2 = Left rounding radius

• rt = Deflecting island rounded top radius

• a’ = Extra displacement from main road

• b1 = Distance from top right rounding radius to edge line

• b2 = Distance from top left rounding radius to edge line

• hb = Island width

• hl = Island length

• Rs = Radius

• Kerbstone

• kt = Kerbstone thickness

• rb = Island radius at bottom

• fb = Kerbstone offset at bottom

• Ri = Radius

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