Creating 3-D Steps

When surveying steps, a 2D representation will normally suffice and this can be achieved using a rectangular shape code that has been split into segments using the NS= dimension.  However, there are situations where the steps need to be constructed in full 3D.  The Steps options allow you to create steps in 3D.

The Steps 2 Point expects you to have surveyed a point on the edge of the top step and a point on the edge of the bottom step, signified by points 1 and 2 in the diagram below.  The features representing the step edges will be generated perpendicularly to the line between these two points.  After you have defined the two points, you will be asked to indicate two features representing the sidewalls of the steps, signified by lines 3 and 4.  As in this case, one of the sidewall features could be the line between the top and bottom points.

Once these two points and two features have been indicated, the Step Creation dialog box is displayed. 

The Parameters group define the basic step parameters.  The Code field defines the code that will be used for each step.  The points will be in pairs representing either the step edges or corners with the first point having a new feature comma code.  The Number of Steps field defines the number of steps that will be created.  The value that is displayed here is calculated from the plan distance between the two indicated points divided by the value in the Default Step Width field.  The Start Point Number is the first number used for new steps points and the numbers will be prefixed with an S if the Prefix Created Points check box is ticked.

The two values at the bottom of the dialog box are calculated from the two points and the number of steps.  The Width field defines the width of each step from front to back.  The Height field defines the height of each riser.  The Defaults group also contains a check box Generate in 3D.  This allows you to calculate points representing the back of each step.  It will use the value defined in the Offset field so that vertical faces are not generated.  Once the parameters are accepted, the step points will be created, as shown below.

The Steps 3 Point option is very similar to the above option except that you will be expected to have surveyed two points on the top step and one point the bottom step.  The direction of the line between the two top step points will give the direction for the creation of step edges between the sidewalls.