Design Rules and Terms Used

Design Rules and Terms Used

Introduction

In order to get the best out of this software, users must understand how the software works as well as the design conventions which must and/or should be adopted in the design process.

Here are some notes on the best design processes.

Details

Software Data Files

CSD stores data in an external folder for processing, and as a backup if the drawing stops unexpectedly.  More information on this can be found in the CSD General help system.

By default, when a project is started a folder is created at the same location as the current drawing (with a name matching the current drawing name and with -Data added as a suffix).  Project data is stored in this folder.

The folder location can be manually set by the user - see the CSD General help system for more information on how to do this..

Surfaces

Extents

The software works by reading an 'Existing' surface and using these levels to generate an 'EXISTING' surface profile for the Road objects created with the software.

The Existing surface is initially assigned in the Design Settings tab of the Active Drawing Settings form, however it can be edited for any Road object created.

For this to be successful the following criteria MUST be adhered to::

The surface created MUST extend for the full length of EVERY alignment - if the software cannot find 'existing' surface levels at every single station along the alignment you may receive error messages and problems in processing the data using the software.

For Civil 3D customers, a Civil 3D surface is normally set as the 'existing' (or survey) surface from which the design levels are calculated against.

For non-Civil 3D customers, a Surface must be created in Civil Site Design using the Create/Edit Surface command.

Auto Surface Model - Information

By default, CSD creates a surface called TotalModel when the   Auto Surface Model command is run.  Some things to know:

The surface model Build setting has been adjusted to allow crossing breaklines and to use the average level at the point of crossing.  This has been done to allow for widening the feature line of the kerb (when the stations don't match up there is always a small overlap) and because the levels will be so close as to not affect the model.  This speeds up the terrain modeling an suppresses many superfluous 'error' messages upon building the surface

The extents (batter to batter) is automatically determined and typically accounts for any overlaps (bow ties).  If exporting the surface from CSD to make a Civil 3D Surface, the boundary will need to be redefined inside Civil 3D to remove loops.

At the ends of roads, where cul-de-sacs are not provided, the software will tend to put in spurious triangles across to other Roads.  It is recommended to set a Maximum Triangle Length to manage this

Exporting to Civil 3D repeatedly will not delete the existing Civil 3D surface - it will just replace the breakline file used to build the surface.

Alignments

Alignments are integral to the software.  The software works by reading alignments in the drawing to obtain horizontal geometry controls for all features including:

Alignment Type
(Set this Type in the CSD Alignments) Alignment Description Prefix
(required in Civil 3D) How CSD Uses the Alignment

String (general purpose object)) <None Required> EVERY object is a String.  A String is an object that contains horizontal and vertical geometry, with or without attached cross section elements.
A String can be plotted, set out or used in the construction of a surface.

Road r- Roads are special Strings that automatically match levels at intersections and can also be used to connect to Kerb Returns, Cul-de-sacs and Knuckles (elbows).  The profile (vertical grading) can be reviewed and designed using the Vertical Grading Editor.
For intersections to form, Road centreline alignments must either STOP or START at the centreline of another road alignment or cross over another road alignment.

Side Roads 'read' the cross sections of Main Roads at the intersecting point.  There is a 'connection point code' expected on the Main Road to enable connection of the Side Road to the Main Road cross section.

Ker Return k- Kerb returns are special Strings that read and connect to the horizontal and vertical geometry from the nominated edge of Road code (the 'connection point code') of a Main and Side Road at an intersection.  They are automatically incorporated into an Automatic Road Model.
Note: the software can automate the kerb return creation process INCLUDING creation and editing of the alignment, using one of the following commands:

Automatic Kerb Returns: This command generates kerb return alignments at all Road intersections, using a single radius, and also creates an existing surface and DESIGN profile for each kerb

Create/Edit Kerb Return: This command creates or edits a single kerb return at an intersection when the user selects the location.  The kerb return is defined with a single radius.  As well as creating the alignment the existing surface profile and a DESIGN profile are also generated for the kerb return

For most cases, using the automated processes will be far easier and more efficient than creating and/or editing the alignment manually.

Cul-de-sac cds- Cul-de-sacs are special Strings that read and connect to the horizontal and vertical geometry of a Road, by matching to a selected Code on the connecting Road.  They are automatically incorporated into an Automatic Road Model.
Note: the software can automate the cul-de-sac creation process INCLUDING creation and editing of the alignment

Create/Edit Cul-de-sac: This command generates or edits cul-de-sac alignments with various cul-de-sac configurations, as well as setting the cross section for the cul-de-sac and the parameters for the vertical design

For most cases, using the automated processes will be far easier and more efficient than creating and/or editing the alignment manually.

Knuckle n- Knuckles are special Strings that connect to a selected Code on a Road.  They automatically match to the Road Code, and automatically trim out the Road overlapping codes at the time of constructing an Automatic Road Model.
Note: the software can automate the knuckle creation process INCLUDING creation and editing of the alignment

Create/Edit Knuckle: This command generates or edits cul-de-sac alignments with various cul-de-sac configurations, as well as setting the cross section for the cul-de-sac and the parameters for the vertical design

For most cases, using the automated processes will be far easier and more efficient than creating and/or editing the alignment manually.

Roundabout <None Required> These alignments must exist already before starting the Roundabout command.  An inner (island) and outer circulating carriageway alignment is expected for the Roundabout command.

Off Ramp l- Can be used to form a linking road between other CSD design objects (normally Roads).  This type of object can be useful in the construction of off ramps and other 'joining' objects

Alignment Geometry

Geometrically, the alignment needs to be connected.  Civil 3D allows you to have unconnected alignments, however this will not be accepted by the Civil Site Design software.

Intersections

The Centreline of Side Road alignments should ALWAYS be SNAPPED onto the Centreline of any Main Road alignment - otherwise the software may not interpret them as 'connecting'

Road Centrelines should no have kinks in the alignment - direction changes should be supported with horizontal curves.  If there are direction changes without horizontal curves, kerb return geometry can fail.

Crossing Alignments are acceptable in the software

For Every Intersection, there must be sufficient alignment length in every direction from the intersection point.  The general rule is to have alignment lengths extending beyond the intersection point of length AT LEAST two times the radius of the kerb returns to be created at the intersection.  This is required for the level sampling required to generate the kerb return profiles and for the software to iterate along the Main and Side Road corridors to locate a kerb return alignment connecting to both road edges and tangential to the corridor centrelines

Alignments, in general, should be at least 30 metres (100 feet) long to satisfy most intersection requirements (this can go much lower depending on the cross section sampling frequency and the radius of any kerb return alignments.

Loop Roads

Alignments that loop back on themselves (such as a 'P' shaped alignment) are currently not supported by the Kerb Return routines.

Looped road alignments can be broken into two alignments at a convenient point so that there is not a loop. In order to ensure continuity, the Designer will need to ensure the vertical grading matches at the beak point, otherwise the rest of the processing works as normal.

Other Considerations

Do not create alignment for Roads that lie on top of one another - this will create additional intersections and kerb returns which will cause the software to build invalid models.

It is recommended that Designer give their alignments the name that they want to have for the Roads - the software will set the Road names to match alignment names.  There is a command enabling renaming of Road alignments.

Each alignment must be FULLY contained within the 'Existing' surface for the entire length of the alignment

In Civil 3D, Station Equations are NOT supported by Civil Site Design - expect unusual results or errors if station equations are used.  It is however acceptable to use a different Starting Station for the alignment (instead of the starting station being zero)

In Civil 3D, never use the Civil 3D Reverse Alignment command - Civil Site Design is not designed to cater for the alignment changes made after this routine has been run

Automated intersection detection and attachment of Cul-de-sacs and Knuckles

Civil Site Design has been set up to permit automatic processing of Intersections, Cul-de-sacs and Knuckles.

The automated processing is substantially quicker than trying to do things manually and it allows for a great deal of flexibility in the profile design. Any modification to a critical road in the vertical or horizontal sense can be carried through to all dependent road objects in a matter of seconds.

In order to make the automated processing work, the software makes use of the feature lines that define the edge of the road, coded as EB by the previous software.  The Designer, however, has complete control over the feature line code (or label) used to define the edge of the road, since the designer creates Templates using Civil Site Design.  These typical cross sections (or templates) are created within Civil Site Design and can be applied to any road in your project.  These special assemblies can also be made 'public' and available to copy locally to any project - once the library of typical cross sections is developed it can be used multiple times.

The connection point label used for the road corridors to define the edge of the road is set in the Connection Point Codes tab of the Active Drawing Settings

Subgrade Layers at Intersections - Kerb Returns, Roundabouts, Knuckles and Cul-de-sacs

In order for the kerb returns, cul-de-sac, knuckle and roundabout cross sections to be able to stretch out into the intersection areas AND include subgrade layers for the pavement, designers MUST include in the relevant templates (see Create/Edit Templates) a Code information to accommodate this.  More information in the Templates command.

A special Code is used by the software to match up to interesection geometry as follows:

Kerb Returns

Clockwise Direction: the kerb return cross section should include a Code called LDUM - this will connect to the edge of the main road and the centreline of the side road.

Anti-Clockwise Direction: the kerb return cross section should include a Code called RDUM - this will connect to the edge of the main road and the centreline of the side road

Cul-de-sacs

Clockwise Direction: the cul-de-sc cross section should include a Code called RDUM - this will connect to the edge of the main road and the centreline of the side road.

Anti-Clockwise Direction: the cul-de-sac cross section should include a Code called LDUM - this will connect to the edge of the main road and the centreline of the side road.

Knuckles

Either LNUK or RNUK depending which side you need the pavement to stretch

Kerb Alignment Naming Conventions

The default naming convention for Kerb Return alignments is as follows:

For non-crossing alignments:
'Main Road Corridor' - 'Side Road Corridor' - Start/End of the Side Road corridor - Left/Right of the Side Road corridor.

eg: MainOne-SideOne-Start-L, defines the location to be at the intersection of the MainOne and SideOne corridors at the start of the SideOne alignment and on the left of the SideOne alignment

For crossing alignments:
At a cross roads, the software creates a point and gives it a number.  This point remains for the whole job and any intersection within 10 metres (30 feet) of that point will use that point number in the identification of the kerb.  The convention is the same as for non-crossing alignments but the point number is now appended:

''Main Road Corridor' - 'Side Road Corridor' - Start/End - Left/Right of the Side Road corridor - P#, where # is the number of the intersections working from the start of the Side Road corridor.

In the case of a crossing road, the software names the intersection as if the side road was split in two.  Therefore, the Start is considered to be where the side road is leaving the intersection with the main road, and the End is considered to be where the side road is approaching the main road.

eg: MainOne-SideOne-End-L-P1, defines the location to be at the intersection of the MainOne and SideOne corridors at the approach to the MainOne corridor on the left, for the first intersection encountered working from the start of the SideOne alignment

Special Note:: If the Designer moves the alignments so that the intersection point goes outside a 10 meter (30') radius from the original location, then a new point is created and the system will go looking for a new kerb return alignment and corridor (because essentially you are creating a new design).

Definitions/Terms Used

Australian Terminology Some international Terms: Definition/Comment

Naturestrip Boulevard Generally regarded as the area between the curb (kerb) and the sidewalk (footpath).  This is normally a grassed or landscaped area.

CL, Centreline Centerline This is where Road Objects connect to the alignment (offset zero).

Crown This is a special Road Element that:

Connects to the edge of a Road at it's start and end, both horizontally and vertically

Trims the end of a Road and enables extension of the Road centerline into the cul-de-sac

Extends the road surface out to the Road centerline at the time of building a surface model.

Cul-de-sacc This is a special Road Element that:

Connects to the edge of a Road at it's start and end, both horizontally and vertically

Trims the end of a Road and enables extension of the Road centerline into the cul-de-sac

Extends the road surface out to the Road centerline at the time of building a surface model.

Kerb Returnn Curb Return This is a special Road Element that:

Connects to the edge of a Road at it's start and end, both horizontally and vertically

Extends out at the time of building a surface model to match the main and side roads.

CW CW Clockwise direction

CCW CCW Counter-Clockwise direction

Batter
Sideslope Daylight The process of linking the design to the target surface.

Table Drain Ditch Specific form of daylighting which provides for a longitudinal drainage function

Edge of Bitumen
Edge of Pavement

Edge of Asphalt
Edge of Travelled Way (ETW) These are terms normally used to describe the edge of Roadway.

Typical Cross-Section
Template Assembly The software includes its own cross section design tool (similar to the Civil 3D Assembly tools) to create cross sections for the Roads and other road elements.

Intersection Defined as the location where two Roads meet.

Elbow Knuckle This is a special Road Element that:

Connects to the edge of a Road at it's start and end, both horizontally and vertically

Can extend out the road pavement or create new pavement in the widening

Extends the road surface out to the original road edge at the time of building a surface model

Long Section
Longitudinal Section

Vertical Grading
height="17" valign="top"Profile Vertical grading design.  A plotted view of the section through surface(s) along an alignment.  The surface can include existing ground, design and subsurfaces.

IPP PVI, VIP, VPI Point of vertical intersection.  This is a vertical design intersection point connecting vertical tangents in a profile.  It is also known as a VPI (vertical point of intersection) and IP (intersection point)

Road Object Civil Site Design works with Roads, Curb Returns, Cul-de-sacs, Knuckles and Roundabouts.  These are collectively known as 'Road Objects' .  In Civil Site Design, roads must connect up at intersections with matching levels and with the 'main' road width protected from adjustment by any 'side' road.
A road is considered for any alignment that has been defined using r- in the prefix of the alignment Description.

Road In Civil Site Design, a Road is an object (normally) describing the roadway and associated cross section elements for the movement of pedestrians and vehicles.
Roads that intersect automatically match levels for the roadway (pavement), as you would expect if you were driving a real roadway.  There are two types of Roads - Main Roads and Side Roads.  By default, the roadway of the Main Road is unadjusted at the intersection, whilst the roadway of the Side Road is automatically adjusted to match up to the Main Road roadway cross section at the intersection.

A road is considered for any alignment that has been defined using r- in the prefix of the alignment Description.

Main Road          A Main Road is defined as a Road with a pavement (roadway) cross section that is unaltered through the intersection zone.

Side Road A Side Road is defined as a Road where the profile and cross section is adjusted to match up to the edge of the Main Road pavement.

Main and Side Road Interaction Main and Side Roads are automatically defined by the alignment geometry for T junctions.  For crossing roads the side road is assigned by the user.  Examples of main and side roads as they affect corridor creation are as shown:


Pavement Roadway, Carriageway Area designated for the movement of vehicular traffic

Roundabout A roundabout is just a collection of alignments and profiles that the user selectively 'trims' in the intersection where the roundabout island and circulating carriageway reside.
Civil Site Design provides a user interface to select and trim back the unwanted components of the roads and curb returns in the roundabout area.

Batter Side slope

Footpath Sidewalk Area designated for the movement of pedestrian traffic.

Chainage Station This is a measure of cumulative plan distance along a profile, alignment or string.

Alignment Type (Set this Type in the CSD Alignments)	Alignment Description Prefix (required in Civil 3D)	How CSD Uses the Alignment
String (general purpose object))	<None Required>	EVERY object is a String. A String is an object that contains horizontal and vertical geometry, with or without attached cross section elements. A String can be plotted, set out or used in the construction of a surface.
Road	r-	Roads are special Strings that automatically match levels at intersections and can also be used to connect to Kerb Returns, Cul-de-sacs and Knuckles (elbows). The profile (vertical grading) can be reviewed and designed using the Vertical Grading Editor. For intersections to form, Road centreline alignments must either STOP or START at the centreline of another road alignment or cross over another road alignment. Side Roads 'read' the cross sections of Main Roads at the intersecting point. There is a 'connection point code' expected on the Main Road to enable connection of the Side Road to the Main Road cross section.
Ker Return	k-	Kerb returns are special Strings that read and connect to the horizontal and vertical geometry from the nominated edge of Road code (the 'connection point code') of a Main and Side Road at an intersection. They are automatically incorporated into an Automatic Road Model. Note: the software can automate the kerb return creation process INCLUDING creation and editing of the alignment, using one of the following commands: Automatic Kerb Returns: This command generates kerb return alignments at all Road intersections, using a single radius, and also creates an existing surface and DESIGN profile for each kerb Create/Edit Kerb Return: This command creates or edits a single kerb return at an intersection when the user selects the location. The kerb return is defined with a single radius. As well as creating the alignment the existing surface profile and a DESIGN profile are also generated for the kerb return For most cases, using the automated processes will be far easier and more efficient than creating and/or editing the alignment manually.
Cul-de-sac	cds-	Cul-de-sacs are special Strings that read and connect to the horizontal and vertical geometry of a Road, by matching to a selected Code on the connecting Road. They are automatically incorporated into an Automatic Road Model. Note: the software can automate the cul-de-sac creation process INCLUDING creation and editing of the alignment Create/Edit Cul-de-sac: This command generates or edits cul-de-sac alignments with various cul-de-sac configurations, as well as setting the cross section for the cul-de-sac and the parameters for the vertical design For most cases, using the automated processes will be far easier and more efficient than creating and/or editing the alignment manually.
Knuckle	n-	Knuckles are special Strings that connect to a selected Code on a Road. They automatically match to the Road Code, and automatically trim out the Road overlapping codes at the time of constructing an Automatic Road Model. Note: the software can automate the knuckle creation process INCLUDING creation and editing of the alignment Create/Edit Knuckle: This command generates or edits cul-de-sac alignments with various cul-de-sac configurations, as well as setting the cross section for the cul-de-sac and the parameters for the vertical design For most cases, using the automated processes will be far easier and more efficient than creating and/or editing the alignment manually.
Roundabout	<None Required>	These alignments must exist already before starting the Roundabout command. An inner (island) and outer circulating carriageway alignment is expected for the Roundabout command.
Off Ramp	l-	Can be used to form a linking road between other CSD design objects (normally Roads). This type of object can be useful in the construction of off ramps and other 'joining' objects

Australian Terminology	Some international Terms:	Definition/Comment
Naturestrip	Boulevard	Generally regarded as the area between the curb (kerb) and the sidewalk (footpath). This is normally a grassed or landscaped area.
CL, Centreline	Centerline	This is where Road Objects connect to the alignment (offset zero).
Crown		This is a special Road Element that: Connects to the edge of a Road at it's start and end, both horizontally and vertically Trims the end of a Road and enables extension of the Road centerline into the cul-de-sac Extends the road surface out to the Road centerline at the time of building a surface model.
Cul-de-sacc		This is a special Road Element that: Connects to the edge of a Road at it's start and end, both horizontally and vertically Trims the end of a Road and enables extension of the Road centerline into the cul-de-sac Extends the road surface out to the Road centerline at the time of building a surface model.
Kerb Returnn	Curb Return	This is a special Road Element that: Connects to the edge of a Road at it's start and end, both horizontally and vertically Extends out at the time of building a surface model to match the main and side roads.
CW	CW	Clockwise direction
CCW	CCW	Counter-Clockwise direction
Batter Sideslope	Daylight	The process of linking the design to the target surface.
Table Drain	Ditch	Specific form of daylighting which provides for a longitudinal drainage function
Edge of Bitumen Edge of Pavement Edge of Asphalt	Edge of Travelled Way (ETW)	These are terms normally used to describe the edge of Roadway.
Typical Cross-Section Template	Assembly	The software includes its own cross section design tool (similar to the Civil 3D Assembly tools) to create cross sections for the Roads and other road elements.
Intersection		Defined as the location where two Roads meet.
Elbow	Knuckle	This is a special Road Element that: Connects to the edge of a Road at it's start and end, both horizontally and vertically Can extend out the road pavement or create new pavement in the widening Extends the road surface out to the original road edge at the time of building a surface model
Long Section Longitudinal Section Vertical Grading	height="17" valign="top"Profile	Vertical grading design. A plotted view of the section through surface(s) along an alignment. The surface can include existing ground, design and subsurfaces.
IPP	PVI, VIP, VPI	Point of vertical intersection. This is a vertical design intersection point connecting vertical tangents in a profile. It is also known as a VPI (vertical point of intersection) and IP (intersection point)
Road Object		*Civil Site Design* works with Roads, Curb Returns, Cul-de-sacs, Knuckles and Roundabouts. These are collectively known as 'Road Objects' . In *Civil Site Design*, roads must connect up at intersections with matching levels and with the 'main' road width protected from adjustment by any 'side' road. A road is considered for any alignment that has been defined using r- in the prefix of the alignment Description.
Road		In *Civil Site Design*, a Road is an object (normally) describing the roadway and associated cross section elements for the movement of pedestrians and vehicles. Roads that intersect automatically match levels for the roadway (pavement), as you would expect if you were driving a real roadway. There are two types of Roads - Main Roads and Side Roads. By default, the roadway of the Main Road is unadjusted at the intersection, whilst the roadway of the Side Road is automatically adjusted to match up to the Main Road roadway cross section at the intersection. A road is considered for any alignment that has been defined using r- in the prefix of the alignment Description.
Main Road		A Main Road is defined as a Road with a pavement (roadway) cross section that is unaltered through the intersection zone.
Side Road		A Side Road is defined as a Road where the profile and cross section is adjusted to match up to the edge of the Main Road pavement.
Main and Side Road Interaction		Main and Side Roads are automatically defined by the alignment geometry for T junctions. For crossing roads the side road is assigned by the user. Examples of main and side roads as they affect corridor creation are as shown:
Pavement	Roadway, Carriageway	Area designated for the movement of vehicular traffic
Roundabout		A roundabout is just a collection of alignments and profiles that the user selectively 'trims' in the intersection where the roundabout island and circulating carriageway reside. Civil Site Design provides a user interface to select and trim back the unwanted components of the roads and curb returns in the roundabout area.
Batter	Side slope
Footpath	Sidewalk	Area designated for the movement of pedestrian traffic.
Chainage	Station	This is a measure of cumulative plan distance along a profile, alignment or string.