Civil 3D Introduction · Civil 3D Introduction • Points are data collected by surveyors which represent existing site conditions (elevations, boundaries, utilities, etc.).

Civil 3D Introduction

• Points are data collected by surveyors which represent

existing site conditions (elevations, boundaries, utilities,

etc.).

• Each point is numbered (or named) and has a label

indicating specific information (usually the elevation and

description), and has coordinates (northing and easting).

• Each point is a single object (node) with a point style and a

point label.

• Points can also be used to represent proposed or final site

conditions.

• At present, there are no standards for point descriptions.

Points Overview

Points Overview

• Point Marker Styles

– On the Settings Tab in

Toolspace, expand the

Point Styles Container,

right-click, then edit the

point style of interest.

– Note that there are many

different point styles, each

representing a different

structure.

– A point style defines the

display, elevation, and

marker size.

Points Overview

• You can then select the marker, size, etc.

Points Overview

• On the Prospector tab in

Toolspace, you can right-

click on the desired point

group, and select Properties

to edit the display of the

point information.

• In this case, the marker,

point number, and elevation

are displayed (I do not have

a description for this point).

Points Overview

• You can also subdivide your

points into specific groups

for further display and

analysis (such as existing

ground, utilities, boundaries,

trees, etc.).

• Description keys and point

groups help to automate

point layers and allow you to

manage points with similar

purposes.

Creating Points

• A common way to bring elevation data into C3D is to import the

points from a data file.

• This data file must have the point number, northing, easting,

elevation, and description (if needed).

• These files can be comma or space delimited, and arranged in

various manners.

• As an example, if the file format is listed as PENZD, the first

number is the point number, the second number is the easting,

the third number is the northing, the fourth number is the

elevation, and the fifth number is the description.

• You must be informed of the format used (ENZ, NEZ, PENZ,

PNEZ, etc.).

Creating Points

• As an example, the following file is in comma

delimited, PNEZD format, even though not all points

will have a description:Point Number, Northing, Easting, Elevation

Points Creation

Points Creation

• The command on the far right allows you to import

points from an external data file.

Points Creation

• Click the “Plus” sign

to browse for you

point file:

• Scroll down to select

the proper file

format:

• Click on the box to

“Add Points to Point

Group”

Points Creation

• Then click on the

“Plus” sign and give

the point group a

unique name.

• Notice that the point

group name is now

populated in your

window.

• Click OK.

• Zoom out so you

can see the

imported points.

• Notice that the

“Existing Ground”

Points are now

added to the

Toolspace.

Points Creation

• Surfaces are 3D objects representing topography.

• They are commonly created from point groups.

• They can be used to examine water flow and earthwork.

• Surfaces may need to be edited for accurate representation.

– Adding break lines.

– Swap Edges.

– Others include minimizing flat areas, raising/lowering surfaces,

• Two types of surfaces:

– Triangulated Irregular Network (TIN):

• Most common.

• Triangulated surfaces, with surface points connected by straight lines.

– Grid:

• Interpolates and assigns data to each grid intersection.

• Ex. Digital Elevation Models (DEM)

Surfaces

• Continue with the

same file used to

create points.

• From the Home

tab, Create

Ground Data

palette, select

Surfaces, Create

Surface.

Surface Creation

• Edit the name of the

surface to “Existing

Ground:”

• You can click the

ellipsis to edit the style

of contour lines you

desire:

• Click “OK.”

Surface Creation

• At this point, the surface will

not be visible because it is

not linked to a point group.

• In the Toolspace Prospector

Tab, expand the Surfaces

container, then Existing

Ground, and finally

Definition.

• Right-click on Point Groups

and Add.

Surface Creation

• In the Point

Groups dialog

box, select

“Existing Ground”

• Click Apply

• Click OK.

Surface Creation

• The surface

representing

the existing

ground will be

created and

should be

displayed.

Surface Creation

Surface Creation

• If your triangles do

not appear:

– Expand the

Surface Styles

container in

Toolspace-

Settings:

– Right click on the

style used and

select Edit:

– Turn the Triangles

on.

• Click on any contour line and a contextual menu will be activated.

• The “Water Drop” command will illustrate the movement of a

theoretical path a drop of water on the surface.

Surface Creation

• The path of the water

is represented by a

2D polyline.

Surface Creation

Alignments

• Alignments are used in most civil engineering

projects to assist with laying out:

– Roads, railways, runways, and bike trails.

– Swales, waterways, utilities, levees, dams, and landfills.

• Alignments are used to represent center lines, lane

boundaries, shoulders, right-of-ways, etc.

• Alignments are custom objects that are similar to

polylines.

– Can contain tangents (line segments), curves, and spirals.

Alignments

• Alignments, profiles, and cross sections provide for a

complete three-dimensional description of the road.

• When laying out a construction site, oftentimes

parcels, polylines, and arcs are used as base

geometry for interior roads.

– These objects are later converted into alignments.

Five Types of Alignments

• Centerline

– Most common.

– Used when the location and design parameters of the

centerline of the road are known.

• Offset

– Used to create transitions within a corridor design.

• Curb Return

– Used to base the road design from the curb.

– Used to connect edges of intersecting roadways.


• Rail

– Used to calculate

curves along chords

rather than arcs.

– Used to set track

width and calculate

cants.

• Miscellaneous

– Used when the

alignment you wish

to create does not

fall into any of the

other categories.


• Notice that you can

utilize the Design

Criteria tab, which

checks your design

against standards.

• If your design

violates the design

criteria, C3D will

alert you.

Creating Alignments in C3D

• On the Create

Design palette,

go to the

Alignment

command.

• You have many

options in which

to create your

alignment.


• Create a polyline (on

the V-ROAD-CNTR

layer) that

represents a road

across the surface

(construction site).

• Make sure there is a

bend in your

proposed road.

• The angle between

the two segments

will later be

converted into a

curve.


• I intend to convert the

polyline into an

alignment.

• Go to Alignment,

Create Alignment from

Objects.

• You will then select the

polyline of interest.

• Press Enter.


• C3D will then

prompt you to

select the direction

of your alignment.

• The Create

Alignment from

Objects menu will

then appear.


• From this menu:

– Give the alignment a

Name.

– Select the Type

(Centerline).

– General tab:

• You can assign the

alignment to a

specific Site.

• Set the Default

radius.

• Erase existing

entities.


• From the Design

Criteria tab:

– Select your Starting

design speed.

– Check the Use

criteria-based

design box

(sometimes does not

design the curve to

the correct length,

but uses the default

values instead).

• Then select OK.


• Notice that your alignment

has been created:

– Proper curve.

– Station labels.


• Notice that the Entry Road

alignment has been added

to the Prospector tab in

Toolspace.

Alignment Hints

• Make sure polylines extend beyond other intersecting

polylines (or come to an exact “T”), as this process

will ensure that intersections are created properly.

• Make sure that at least one intersecting road does

not end at the intersection. Make sure it carries

through.

• While C3D will allow you to create multiple

alignments at once, creating them individually will

allow you to have more control over the design of

each alignment.

Profiles

• A profile is a side view of an alignment, with

elevations shown along the alignment length.

• A profile consists of a profile grid and its annotation.

• In C3D, they are dynamic, geometric objects that

update if either the alignment or surface is altered.

• The next step after creating the alignment is to

produce the profile view.

– This process is significantly easier, and more

intelligent, than doing it in AutoCAD.

Creating Surface Profiles

• From the alignment

exercise where you

created the entry

road on the surface

from “PointsInClass”:

– Go to the Create

Design palette

and select Create

Surface Profile.


• Select the Alignment

you wish to create

the surface profile

for…in our case, we

only have the Entry

Road alignment.

• Select Add.

– Note that the

Existing Ground

surface is added to

the Profile list.

• Click Draw in profile

view.


• Click Next and follow the Create Profile View wizard

to create your profile (in order to accept the default

settings).


Finally, select Create Profile View.


• Click

near the

drawing

to place

the

surface

profile for

the entry

road.


• The completed surface profile.

Creating Design Profiles

• To this point, we have created profile views based on

a surface (Existing Ground).

• Now we will construct a design profile, since very

rarely will the road match up perfectly with the natural

topography.

• We will superimpose both profiles on the same

graph.


• From the Create

Design palette,

select the

Profile

command, then

select Profile

Creation Tools.

• You must then

select the profile

view you wish to

create (left click

on the surface

profile graph).


• The Create Profile

menu will appear.

• Name the profile

something descriptive.

– Profile style:

• Design Profile

– Profile label set:

• Complete Label Set

• Click OK.


• The Profile Layout Tools menu will appear.

• Select the Curve Settings option.

• The Vertical Curve Settings menu will appear (select defaults).

Then click OK.

-The K-Value is the horizontal

distance required to achieve a 1%

change in the slope of the vertical

curve.

-K-Values for various speeds are

provided in AASHTO Green Book

(A Policy on Geometric Design of

Highways and Streets).

-Crest Curves are curves that

convex upwards (ex. curves at hill

crests and when uphill grades

becomes less steep).

-Sag Curves are curves that

concave upwards (ex. curves at

valley bottoms and when uphill

grades become steeper).


• Then select Draw Tangents With Curves from the Profile

Layout Tools menu.

• Create the design profile by drawing on the surface profile

graph.


• When you are finished selecting points to create your

design profile, press Enter.

• Your design profile should now appear on your

surface profile graph.

• Close the Profile Layout Tools menu when you are

finished.


• Finished profile graph.

• Notice that the grade

and stations are

labeled.


• The PVI is the “Point of

Vertical Intersection,”

where grade lines

intersect.

• LVC is the length of the

vertical curve.

Assemblies

• An assembly defines the attachment point of a

roadway cross-section to the horizontal and vertical

alignments.– Undivided Crowned Road

– Undivided Planar Road

– Divided Crowned Road

– Undivided Planar Road

– Railway

– Other

• Subassemblies represent individual components of

the proposed cross-section (such as a lane or curb).

Corridors

• A corridor is a 3D model of a proposed design based

on alignments, profiles, and assemblies.

• Corridors can be used to represent a single

alignment, profile, and assembly (such as a single

road) or can contain multiples of each.

• When modeling intersections, it is good practice to

have all intersecting roads as part of the same

corridor object.

Intersections

• Intersections are complex corridor models that

automatically create offset and curb return geometry

where two intersecting alignments meet.

• Geometry is automatically updated should the

alignment, profile, assembly, or surface is altered.

• Four intersection objects possible:– Create Intersection

– Create Roundabout

– Add Approach

– Add Turn Slip Lane

Intersections

• Using a file with a

created surface,

enclose the entire

site with a polyline

and give the site a

name

Intersections

• Create a parcel from

the polyline you just

created.

• Make sure you choose

the label style “Name

Square Foot & Acres,

Automatically add

segment labels, and

erase existing entities.

Intersections

• Create alignments for each of the proposed roads you

drew as polylines.

Intersections

• I created alignments for 19th Street and Avenue A.

• Notice that they appear in your prospector tab.

Intersections

• Create Right of Way Parcels.

• Remember you have to

select the parcel label.

• Use the default values.

Intersections

• Now create

the surface

profile for

each

alignment.

Intersections

• Next, create the design

profile:

– Select Profile

Creation Tools, then

left click on the

profile, then the

Create Profile menu

will appear.

Intersections

• Now draw the

desired design

profile directly on

the profile view.

Assemblies

• Now we will

create an

assembly.

• You should

place the

location and it

will zoom to

the centerline

where the

roadway will

be built.

Assemblies

• Click on the centerline.

• Select Tool Palette

from the contextual

menu.

• Then select the Basic

Tab.

Assemblies

• Click on BasicLane

and check

parameters.

• Place the left and right

lanes.

Assemblies

• Repeat the process to add shoulders, curbs, grade to

daylight, etc.

• Repeat the process for the other roads.

Corridors

• Select Corridor.

• Then make sure

alignment, profile, and

assembly correspond.

Intersections

• Click on Create

Intersection.

• Select the main road.

• Select all crowns

maintained.

Intersections

• Check your

curb return

parameters.

• Then select

create

intersection.

Intersections

• Intersection

Grading

• Grade and Slope are terms used to express the

gradient of land along a line.

– Grade

• Usually expressed as a percent.

– Slope:

• Usually shown as a ratio of the change in altitude (ΔVd)

to change in horizontal distance (ΔHd).

Grading

• Feature Lines

– Complex, linear objects that represent a string of known

elevations, such as the perimeter of your site.

– They can be drawn, or converted from existing objects.

– Store horizontal and elevation location data (similar to 3D

polylines).

– Allow modeling of proposed grading operations.

– Minimize amount of elevation points without compromising

design integrity.

– Stepped Offset command can be used to create new

Feature Line by giving vertical and horizontal offset.

Grading

• Grading Groups

– Collections of Feature Lines that form a contiguous whole.

– Can be used to automatically generate 3D surfaces.

– Surfaces created from Grading Groups will appear in the

Prospector tab.

– Feature Lines and Grading Groups are organized by site.

Grading

• From a previously created

surface:

– Using the Polyline

command, create a border

for your building pad.

• My example was a 200’

square pad located on a point

of interesting topography (not

realistic, but will show grading

more obviously).

Grading

• The next step is to create a

Grading Group.

• From the Create Design

palette, select the Grading

command, then Grading

Creation Tools.

• Click the arrow to expand the

menu.

Grading

• Select the first icon, to Set the

Grading Group.

• From the Create Grading

Group menu:

– Give the grading group a

name.

– Check Automatic surface

creation.

– Check Use the Group Name.

– Check Volume base surface

(for calculating volumes later).

Grading

• The Create

Surface menu will

appear.

• Check the

settings. If all

looks correct, click

OK.

• Note that Building

Pad is now added

to the Prospector

tab.

Grading

• Select the target

surface.

• In our case, we will

grade to the Existing

Ground surface.

• Then, change the

grading criteria to

Grade to Surface.

Grading

• Select Create

Grading.

• Select the building pad

and the Create

Feature Lines menu

will appear.

– Give the Feature Line

a name.

– Check Style.

– Check Erase existing

entities.

– Check Assign

elevations.

• Click OK.

Grading

• The Assign Elevations menu

will appear.

• Assign the desired Elevation for

the building pad.

– I am randomly assigning an

elevation of 35’.

• Then select the grading side,

meaning left-click outside the

building pad boundary.

• You will then be asked to

answer a series of questions.

Grading

• Apply to entire length?

• Cut Format?

– Grade or Slope?

– Give preferred cut slope.

• Fill Format?

– Grade or Slope?

– Give preferred fill slope.

• Note: Cut and fill slope are dependent on the soil properties!

– Clay soils commonly use slope ratios of 2:1 to 3:1.

Grading

• Grading will appear.

• We will now need to add

infill to represent hole in

surface where building

pad exists.

Grading

• Select the area to

infill.

• Notice that a

diamond will appear.

Grading

• In order to view our

surface three-

dimensionally, left-click

on the surface and a

contextual menu will

appear.

• Select the Object

Viewer command.

Grading

• Select Conceptual.

• Using the View Cube,

place the surface in an

orientation that

maximizes your

understanding of the

surface you just

created.

Grading

• From the Grading

Volume Tools menu:

– Select Grading Volume

Tools.

• The Grading Volume

Tools window will then

appear, giving a

preliminary report.

Grading

• Notice that in my

example, the net

amount of earthwork

is 16,888.69 yd3 of fill.

• We can adjust the

building pad level to

balance out the

cut/fill, if design

requirements allow.

– The building pad

may be required to

reside at a set

elevation to remain

above the flood

plain.

Grading

• We can adjust the building

pad level in 1.00’

increments…and the

drawing should

automatically update to

reflect your changes.

• I lowered the building pad

level by 6 feet to minimize

the amount of

earthwork…now the net is

321.25 yd3.

Grading

• Or you can use the Automatically raise/lower to balance the

volumes tool.

• You can then minimize the required volume.

Grading

• The new earthwork

volumes:

• Note that the

building pad

elevation was

moved fro 35’ to

28.881’.

Grading

• We need to

incorporate both

surfaces (Building

Pad and Existing

Ground) into a

finished surface.

• Use Create Surface:

– Give it a name.

– Click OK.

Grading

• Expand the Surface

container to reveal the

Finished Surface

Definition.

• Right-click on Edits

and select Paste

Surface.

Grading

• The Select Surface

to Paste menu will

appear.

• Select Existing

Ground first and

click OK.

• Repeat the process

to add the Building

Pad surface.

Grading

• At this point, we have

three surfaces, and we

will only display the

finished surface.

• Right-click on the

Existing Ground and

Building Pad surfaces in

Prospector and select

Surface Properties.

• Change the Surface style

to No Display.

• Click Apply and then OK.

Grading

• Notice that the

contour lines

incorporate all three

surfaces.

• Using the Object

Viewer, the building

pad can be located.

Civil 3D Introduction · Civil 3D Introduction • Points are data collected by surveyors which represent existing site conditions (elevations, boundaries, utilities, etc.).

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