4.1 Corridor Creation

A corridor model is created by applying a template to selected horizontal and vertical geometry.

Corridor models are created by choosing the New Corridor command from the Corridors tab, or by selecting an alignment and choosing the Create Corridor command from the pop-up menu. When the command is selected, the software will step you through a series of prompts. These prompts appear on the cursor and can also be defined using the Tool Settings dialog.

Create Cooridor - Screen Shot

You are prompted to define the following parameters:

Locate Profile – Reset For Active Profile - Select the profile name from the drop-down list or issue a reset button to accept the Active Profile that is defined for the Horizontal Alignment.

Corridor Name - Define the name for the corridor. It is recommended that you use same name as the horizontal alignment.

Design Stage - Design stages are used to define a variety of parameters to control the template drop interval as well as which elements are drawn in the 3D model (3D line strings, 3D components, surface meshes, etc). The design stages are defined in CV_Highway_Features_Levels_ElemTemp.dgnlib which is attached by a configuration variable.

The design stages can be reviewed in the Civil Standards tab of the Project Explorer dialog as shown below.

Design Stages - Explorer Menu

The design stage can be changed at any time throughout the corridor modeling process.

Each design stage is defined to provide more detailed information as you work from conceptual design for the final design. The settings for each design stage are defined in the CTHDOT standards and vary for each design stage.

Template Drop Interval Multiplier - When templates are applied to the horizontal and vertical geometry, the user is prompted to enter a template drop interval. CTDOT recommends an interval of 5. The Template Drop Interval Multiplier parameter is used to specify a multiplier, which is applied to the initial template drop interval, to determine the actual interval of each template drop location according to the selected design stage. This is useful to speed up processing for early design stages where less detailed information is required. The CTDOT design stages have been defined with the multiplier values shown in the table below.


Design Stage

Template Drop Interval Multiplier








After defining the Profile, Corridor Name, and Design Stage, you are prompted to define the Template Drop information as shown below.

Create Template Drop - Dialog Box

The parameters can be defined in the Create Template Drop window, as shown at above, or by dialogs floating on the cursor that will step you through the parameters.

Each parameter is defined below:

Lock to Start - Toggle this option on to lock the start of the corridor to the start of the horizontal alignment.

Start - Define the Start station for the corridor.

Lock to End -Toggle this option on to lock the end of the corridor to the end of the horizontal alignment.

End - Define the end station for the Corridor.

Drop Interval - This parameter is used to define the interval that the template will be applied to the corridor. We recommend a Drop Interval of 5 for CTDOT projects.

Minimum Transition Before Drop / Minimum Transition After Drop - If they are non-zero, then a transition drop is created at the beginning/end of the template drop with a length greater than or equal to the value entered. The actual length is determined by how far it is between the new drop and the drop before/after the new drop. If there isn't enough space to meet the minimum, then the previous/next drop is shortened to accommodate the transition. If there is no previous/next drop, then no transition drop is created.

Template - Define the template from the library to be applied to the alignment and profile. The … button to the right of the template name is used to browse the template library to choose the desired template.

After defining the Create Template Drop parameters, the template is applied to the selected horizontal and vertical alignments to create the corridor. A 3-Dimensional model named Design-3D is automatically created in the active design file and referenced to the active model.

Note: The referenced graphics are not always desirable and can be turned off using the MicroStation Reference Attachment tools.

Different views can be displayed by holding down the right-mouse button in the MicroStation view until the pop-up menu appears, and then choose the desired layout.

View Control 3 Views Plan Profile 3D - Tool Selection

3 Views Plan Profile 3D - Screen Shot

In addition to the 3d graphics, 2d graphics are drawn in the active model as described below:

  • 2-Dimensional graphics are drawn in the active model as defined by the features assigned to the individual points in the template. The CTDOT feature definitions that are assigned to points on the surface of the template, such as the edge of pavement, shoulder, or ditches, are the only template features that draw these 2D plan graphics.
  • Graphics representing the length of the corridor model and the template drop range are created in the active model. This graphic includes several “handles” at intervals along the length of the corridor that can be easily selected to identify the corridor model as shown below.

Handles and Ranges for Cooridor - Screen Shot 


  • The corridor is added to the OpenRoads Model, which can be reviewed in the Project Explorer dialog.

Final Design Stage for Corridor - Explorer Menu