Superelevation Shapes

This exercise demonstrates how to manually create superelevation shapes in a drawing using the Superelevation Shape Maker tool. The tool will create superelevation shapes that are meant to be used along with automated superelevation shapes or can be used with other manually created superelevation shapes.  The drawing elements in the shape file represent the roadway superelevation and are necessary to run proposed cross sections.

To begin open the shape dgn file, XX####_SHP.dgn. The manually created shapes reside in the dgn shape file defined in the working alignment.

Next, Open the Project Manager, then go to Directory>Current Working Directory, next Select the desired project (.prj file) ,  then Select OK, and then Select user (name) from Project Users menu.

Verify the proper working alignment is being used, then Select Superelevation Shapes tab on the Project Manager menu.  OR...
Project Manager menu with Superelevation Shapes tab

Alternatively, the Project Manager is not necessarily needed for this exercise  The Superelevation Shape Maker can be accessed from the Tasks bar> Road Tools menu.
Road Tools task bar with Shape Maker icon

The Superelevation Shape Maker menu will appear. Select Job Number and set Tolerance to 0.03 and zoom into the area were the manual shape will be created.
Superelevation Shape Maker menu

Shape Parameters.
The shape parameters must match the shape cluster, chain/profile, definition used in the Automated Superelevation tool under Calculate Superelevation.

Superelevation Shape Maker menu, Shape Parameters fields

To auto-populate Shape Parameters fields , first select Identify Shape button, next, select the proposed roadway shape in the dgn that is adjacent to shape that is going to be created. This will load matching parameters.  Verify Shape Parameters settings accordingly.

Draw Shape Extents
To use the automatic method, the extents of the proposed shape must be defined before the final shape is created. The success of creating a manual shape relies on laying out the shape extents using MicroStation element.  The following presents a typical use of a manually created shapes.

Shown is a given typical existing turnout with edge of pavement and shoulder.  The design roadway superelevation shapes can also be seen.. The design calls for a formal paved turnout approximating existing turnout extents.  Note the turnout starts in a spiral and ends within a curve at a full super rate of 6%.  For this example, the turnout shape has been determined to start at a -2% (out sloped) and transition to -1% at the full superelevation point and then maintain -1% the remaining length of the turnout.  This will keep the rollover under 8 in the full super section of the curve with respect to the turnout.

Drawing showing typical existing turnout with edge of pavement, shoulder, proposed centerline with stationing, and proposed roadway superelevation shape

Shown next, are MicroStation elements drawn to represent the turnout extents and construction linesThe necessary line work to create a superelevation shape are the turnout extent lines (green) and the filler lines (red).  Note the station and offsets.  The process is as follows;

Drawing of proposed turnout extents with filler lines and station callouts

Begin by drawing the extents of the turnout. The Draw Transition tool is best used to draw the inside of the turnout shape boundary and works well drawing other extent lines. The two shapes must be coincident were they meet.  Overlaps and gaps will cause an error in the cross section run.

Next, Draw the Filler lines.  Draw the filler lines perpendicular to the center line.  The length must extend the shape width.  The desired cross slope will be distributed along the length of the filler line.  Note the Filler lines are located inside the proposed shape boundaries  This is necessary for a skewed shape. The filler lines will define the begin and end transition stations.

Filler Lines
This entire demonstration will show two shapes being made.  The first shape will be start a transition from -2% to -1% and the second shape will be a constant -1%, as shown.
Drawing of proposed turnout extents with filler lines and proposed slopes and transitions

Once the layout work has been done, go back to the Superelevation Shape Maker menu , select By Line method and select the Transition bo

Next enter slope value for the first filler line, then select ID Line button, then select the filler line in the dgn that will represent the begin transition shape slope.  
Superelevation Shape Maker menu, Filler Lines fields with slope field highlighted

The filler line will highlight. Next, data point in dgn to accept. A Delete button will appear indicating the filler line has been accepted.  The Delete button can be use to delete entries in reverse order that they were entered.
Superelevation Shape Maker menu, Filler Lines fields

Next, enter slope value for the second filler line, then select ID Line button, then select the filler line in the dgn that will represent the end transition shape slope.
Superelevation Shape Maker menu, Filler Lines fields with slope field highlighted

The filler line will highlight. Next, data point in dgn to accept. The ID Line button will disappear and the Draw button will become active. Select Draw.  Next, data point inside the area of the proposed shape, then the busy cursor appear.
Superelevation Shape Maker menu, Filler Lines fields with draw button activated

The shape will be created and appear similar to below.  Note the red circles are at intersection points and are temporarily visualized.  There are many in this example due to the spiral consisting of many tangential sections.
Drawing showing superelevation shape creation with numerous intersection point circles and data point area callout

Note the constructed shape and the slope designation. Zoom in to see other slope designation
Drawing showing created superelevation shape and zoom in area of interest callout

Zoom view shows the shape filler line with the slope.
Drawing showing created superelevation shape area of interest

Repeat process for other shapes.  Final manually created superelevation shapes example shown.  These superelevation shapes will work with proposed cross section runs.
Drawing showing final manually created superelevation shapes

The manually created superelevation shapes will influence the proposed cross sections shown below.

Cross section showing transition of turnout shape
Drawing showing cross section influenced by manually created superelevation shape with transition slope

Cross section showing -1% turnout shape with full super roadway section
Drawing showing cross section influenced by manually created superelevation shape with full slope

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