About Alignment Design Checks

Create design checks to verify the design parameters for criteria that are not included in the design criteria file.

The tables contained in the design criteria file contain the most commonly used criteria for alignment design. Other criteria can be checked by using mathematical expressions known as design checks.

Design checks are created and managed in the same manner as label expressions. Use the Design Check Editor dialog box to create and edit design checks. To apply a design check to an alignment, you must add it to a design check set, which is similar to an alignment label set.

You can create design checks for lines, curves, transitions, and straight intersections, which are groups of multiple line, curve, and transition elements.

Note: Independent elements are checked separately from sub-elements in straight intersection groups. To apply the same design check to both element types, create a separate design check for each type. For example, to enforce a minimum radius for all curves, create a curve design check for use with the independent curves and a straight intersection design check for use with transition-curve-transition groups.

Design checks differ from label expressions in that they always return a true or false value. For example, you can create a design check to issue a notification if a straight is shorter than a specified minimum straight length.

Tutorial Exercise: Working with Design Checks

Design Check Sets

After you create a design check, save it with an appropriate combination of other design checks in a design check set. A design check set can be applied to an alignment either during the alignment creation process, or through the properties of an existing alignment.

A design check set consists of design checks for a combination of design check types. For example, you can create a design check set that consists of separate design checks for minimum and maximum A values for transitions, minimum radii for curves, and minimum transition transition lengths.

Design check sets are created and managed in the same manner as label sets. Use the Design Check Set dialog box to create and edit design check sets.