Create Grading
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Create Grading

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Introduction

Grading Strings are the same as other Strings, with the following differences:

Grading Strings can be used for various design tasks, such as: lot grading, detention basins, building pads, retaining walls and car parks.

Once a polyline is selected for a Grading, a directional arrow is drawn to show the direction of the grading calculations.  Initially, the polyline direction is used for the grading direction.

It is intended for multiple Grading Strings to be built into surfaces using the Model Builder command, to be combined with other grading strings and other design strings.  In the case that the grading forms part of a broader collection of strings forming an overall design surface, it may be preferred to tick on the No Surface option to not create a surface from the grading.

Any 2d polyline on any layer can be used for a grading.  Use this command to convert a 2D polyline into a Grading String.

This form contains three (for Civil 3D users) or four tabs:

Breakline Notes: Overlapping breakline entries is not recommended as unexpected triangulation results can occur.  When breaklines overlap, elevations will be taken from one of the two breaklines.  Breaklines do not need to share any elevations where they cross so triangulation results can be undesirable in overlap situations. 

Notes:

Use the Create/Edit Section (Create/Edit Template) command to create cross sections to apply around the Grading.  After creating the Grading, opening the Design Data Form from the Vertical Grading Editor form for the string will enable editing of the cross section shape along the string length

Use the Paste Surfaces command to create combined TIN surface/s.  This can then be used as a base surface for further design, and to create a single composite surface of designed and existing parts.

Use the Model Builder command to construct user defined surface models combining any and all Strings and codes, with user control over all code trimming for the surface.

When editing in the Vertical Grading tab, a marker will display at the location of vertical PI highlighted in the list of PI's.  The marker displayed is managed in the CSD Settings folder - a drawing file located in the Settings folder named GradingMarkerActive.dwg is applied.  Users can edit this .dwg to change the marker.

Grading and Model Viewer

It is common to use multiple Grading Strings in the construction of an overall surface.  In Model Viewer, rendering is applied to the triangles using the Codes assigned to each triangle edge.  These Codes come from the String cross sections.

Typically, the code C.L. is used to represent the centreline of a road and is rendered accordingly in Model Viewer.  It may be advantageous if the centreline code of Grading is not defined with the code of C.L. to prevent unexpected material rendering results.

If the option is used, users can opt to have a prefix section, main replacement name section and suffix section in the Code.  Format is: prefix@main$suffix

Volumes Tab in Civil 3D

For Civil 3D users, the Volumes tab will not operate unless both the base surface and the grading surface are Civil Site Design surfaces (not Civil 3D surfaces).  Users have two options for obtaining volume information between a grading and base surface:

  1. Use the Civil 3D Surfaces command to create a Civil 3D surface from the grading and then use Civil 3D surface volume tools to compare

  2. Use the C3D to CSD Surface command to convert the Civil 3D 'base' surface into a Civil Site Design surface equivalent.  Once that is done it can be used as the base and the volumes tab will work as expected.

 

Details

Upon selecting the command and graphically selecting a polyline in the drawing, the following form is displayed:
Basic Settings Tab This tab is used for creating Grading Strings and making edits such as changing the Target Surface (surface for batter projections)

 

Grading Controls Sets out the grading string controls to apply when Create/Update is selected
  Name Type in a name for the Grading String.
  Template Assign a cross section Template to apply around the Grading String.
  Edit Template This button opens the Create/Edit Section form.  Inputs are as per the Create/Edit Section command.
  Target Surface Surface to project batters (daylight) to.  Batter positions are calculated at sample intervals along the grading string.
  Initial Elevation Type in an initial elevation for the Grading String.  When the Create/Update button is selected, this value is applied to the string.
  Type Select a location on screen to input the elevation.
  Polyline Length Non-editable field detailing the total length of the selected polyline.
  Spacings Sets the sampling of sections along the grading.  All geometry points of the polyline will be sampled. 
  Corner Angle Increments Angle (in degrees) between sampled sections through an external bend that does not include a horizontal curve.
  Outside Corner Method Set how to treat external bends that don't include a horizontal curve.  Options:
- Radial: Radial 'fan' calculated around the bend, using the Angle Increment at Corners value
- Mitre: Extends the offset codes straight out from their last calculated positions before the bend (using the incoming and outgoing tangent directions) until they meet
- Chamfer: Creates a chamfer (line) running through the bend
- Clover: Creates a clover leaf shape calculating offsets
  Surfaces  
      No Surface Creation If ticked, a surface will not be created directly from the Grading String sections.
      Infill Interior Areas If the Grading String (polyline) is closed, ticking this on will include the internal area in the volume calculation report generated from the Grading form.
      Cut Volume Factor Set to 1 for no change - allows for adjustments to the calculated cut volumes.  Applied in the in the volume calculation report generated from the Grading form.
      Fill Volume Factor Set to 1 for no change - allows for adjustments to the calculated fill volumes.  Applied in the in the volume calculation report generated from the Grading form.
  Name Prefix Adds a prefix to the Name assigned for the string.  Useful for grouping by name.
  Edits  
    Move Select a new position for the grading.  This relocates the polyline and recalculates the grading
    Rotate Select a new rotation for the grading.  This rotates the polyline and recalculates the grading.
    Reverse Reverse the polyline (and grading) direction
  Surface Code Substitution This allows for replacement of the C.L. code with a unique code, to improve material rendering assignment in Model Viewer
    C.L. Replacement Type in a Code to apply instead of 'C.L.'
    Prefix Add a prefix to the Code.  This is separated from the main C.L. Replacement input by a @
    Reverse Add a suffix to the Code.  This is separated from the main C.L. Replacement input by a $
Create/Update Click to create or update the Grading String.  Changes to Template or Initial Elevation will be applied upon updating.
Vertical Grading Tab This tab is used for creating Grading Strings and making edits such as changing the Target Surface (surface for batter projections)
 

Grid View Displays the vertical design in a grid view.  As each item is clicked on a marker is displayed in plan at the vertical PI location. List items are described below
  Distance station along grading string for PI location
  Elevation (Elevation) Elevation of the PI
  Elevation Change Elevation difference from the current PI to next PI
  Back Grade % Grade from the current PI to the previous PI
  Forward Grade % Grade from the current PI to the next PI
  VC Length Type in a vertical curve length to apply at the PI.  Leave at .001 for no Vertical Curve to be applied
Add PI by selection Pick a location in the drawing along the grading string - an PI will be added at that location
Add PI by Reference Adds a vertical PI from a reference point selected in the drawing.
At the command prompt, select a location in the drawing to use as a REFERENCE point for elevations to a new PI.
The following form will display:

List View of Elevations at the location selected.
  Objects Found Lists Surfaces and Strings located in proximity to the selected point
  Station/Station, Offset, Elevation Other columns describe the information type (Ch for station/station, Off for offset from alignment, Lev for elevation/elevation, z for surface elevation).
Users must select an elevation to apply (highlighted with a yellow background)
Select Apply the selected elevation to the x,y position selected.  This sets the Reference Point x,y,z position
Cancel Exit the command without creating a new PI
Set Elevation Tick on to override the elevation to a user specified value.  Type in a value in the cell provided
Show Tick on to draw text for the elevation of the Reference Point
Zoom to Point Zoom to the selected x,y point
Refresh Refresh enquiry tool and drawing display

Upon clicking Select, the user is prompted ('Pick point on String for new elevation) to graphically locate the location along the string C.L. to create the new PI.  Upon selection the following form displays:

Station/Station Confirm the location along the string to create the new PI.  Overtype as required
OK Proceed to next step
Cancel Cancel the command

Upon clicking OK, the user is prompted to select a grade/slope to apply from the REFERENCE Point to the selected location on the string.

Grade 1: or % Slope Toggle to select the method for setting the final elevation of the PI.  Input the value required (note: a Grade of 1:0 is not allowed)
OK Create a new PI
Cancel Cancel the command

Add PI's at horizontal geometry Adds vertical PI's at horizontal geometry points along the polyline.  The following form will display:

Yes Adds extra PI's at the horizontal geometry points, keeping the existing design PI's
No Replaces the current vertical design with PI's only at the horizontal geometry points.
Cancel Do not add PI's at horizontal geometry points
Add PI's to Match Surface Elevations at Selected Sections Creates PI's at all sampled sections around the grading string and sets the elevation of the PI's to match the surface
Delete PI Deletes the first highlighted PI in the grid view
Raise/Lower All PI's Raises/Lowers all PI's by a user defined amount.  Inputs are as follows:

Input Type in an elevation change (positive up, negative down)
OK Apply elevation change
Cancel Do not apply and exit form
Edit Multiple PI's Select multiple rows in a column to edit that column.  Options are:

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  Elevation column cells are highlighted

Input Type in an elevation change (positive up, negative down) to apply to all highlighted cells
OK Apply elevation change
Cancel Do not apply and exit form
 Grade % cells are highlighted

Input Type in a single grade (%) to apply to all highlighted cells
OK Apply grade (%) change
Cancel Do not apply and exit form
  VC Length column cells are highlighted

Input Type in a VC length to apply to all highlighted cells.  VC length will be truncated to prevent overlapping PI's or other VC's as required.
OK Apply elevation change
Cancel Do not apply and exit form
Edit Elevtion by Reference This is an EDIT command.  Before running this command, users must first highlight the PI to edit, then select this command.
At the command prompt, select a location in the drawing to use as a REFERENCE point for elevations to the selected PI.  A graphic line shows the position of the current PI and the mouse location of the reference point.  Click to select the reference point location.
The following form will display:

List View of Elevations at the location selected.
  Objects Found Lists Surfaces and Strings located in proximity to the selected point
  Station/Station, Offset, Elevation Other columns describe the information type (Ch for station/station, Off for offset from alignment, Lev for elevation/elevation, z for surface elevation).
Users must select an elevation to apply (highlighted with a yellow background)
Select Apply the selected elevation to the x,y position selected.  This sets the Reference Point x,y,z position
Cancel Exit the command without creating a new PI
Set Elevation Tick on to override the elevation to a user specified value.  Type in a value in the cell provided
Show Tick on to draw text for the elevation of the Reference Point
Zoom to Point Zoom to the selected x,y point
Refresh Refresh enquiry tool and drawing display

Upon clicking Select, the user is prompted ('Pick point on String for new elevation) to graphically locate the location along the string C.L. to create the new PI.  Upon selection the following form displays:

Station/Station Confirm the location along the string to create the new PI.  Overtype as required
OK Proceed to next step
Cancel Cancel the command


Grade 1: or % Slope Toggle to select the method for setting the final elevation of the PI.  Input the value required (note: a Grade of 1:0 is not allowed)
OK Update the PI elevations
Cancel Cancel the command
Increment Stations Increments all Stations/Stations/Distances for highlighted rows.  Type in an increment and the selected PI's will be shifted by the set amount.
A warning message will display if the shift will result in PI's overlapping any vertical curves or other PI's and the edit will not be applied.

Input Type in an increment (+ or -) to adjust the station/station of the highlighted PI's.
OK Apply increment to chianages/stations.
Cancel Do not apply and exit form
Zoom PI Zooms to the selected PI in the drawing
Zoom All Zooms to the extents of the grading string
Auto Update Tick on to update the Grading Surface and other affected surfaces whenever a change is applied in the grid view. 
Volumes Tab This tab displays volume information for the grading surface.
Note: this command requires two Civil Site Design surfaces.  Civil 3D customers have options (noted in the Introduction section) to obtain volume results.
 

Output View This screen displays the output volumes.  Users can select text from this screen and copy to other applications
Compute Volumes Updates the Output View with volume output data for the current grading design.
Click to update the volume output after making a change to the design
Open Vertical Grading Window This opens the Vertical Grading Editor window to enable graphical editing of the string elevations.
Command inputs are as per the Open Vertical Grading command, with exception to the grid view  icon (this will request the user to refer to the create/edit grading form.
Open Surface Manager Click to open the Surface Manager, to set all display options for the ARD Surface created for the Grading String (as well as any other surfaces and model linework). The full details of this form are described in the Create/Edit Surface command.