Now in the upcoming tutorials they’ll demonstrate how to create and modify alignments you begin creating an alignment by making the location of tangents and points of intersections for the road Center Line alignment during the creation process curves between tangents can be created automatically or added later to accommodate high-speed travel Spirals and super elevation can be added to the curves you can enter numeric parameter values for lines curves and spirals in the alignment entities table if your alignment design must meet minimum standards you can apply design criteria to the alignment either before or after it’s created the upcoming tutorials will demonstrate basic alignment creation tasks in this exercise you’ll use the alignment layout tools to draw an alignment that has curves so first of all go ahead and open up your align-1 drawing in your tutorials folder now this drawing contains a surface that has several circles that are labeled a to d now ensure that your o snap is on by clicking this button right here go ahead and go to your home tab and to your create design panel click the alignment drop down then click alignment creation tools
we’ll get the create alignment layout dialog box let’s start by naming our alignment
type in First Street
now under the general tab select the following settings for site we’re going to keep it at none for alignment style we’re going to leave it at layout the current alignment layer is correct and the alignment label set is correct now note that setting the site to none prevents the alignment from interacting with other objects in the drawing the none selection is helpful when you don’t want Parcels to be created when either intersecting alignments form closed regions or the alignment crosses an existing parcel go ahead and click the design criteria tab the starting design speed value specifies the default design speed at the alignment starting station design speeds can be later specified on other stations along the alignment if no other design speeds are specified the starting speed is applied to the entire alignment we’re going to accept the default starting design speed value for this exercise now the other options on this tab are used only if you want to ensure the alignment design meets specified design criteria do not apply design criteria to the alignment in this exercise you’ll learn how to use the design criteria feature in another exercise go ahead and click ok
now the alignment layout tools toolbar is displayed it includes the controls required to create and edit alignments in the alignment layout tools toolbar go ahead and click this drop down right here select curve and spiral settings now in the curve and spiral settings dialog box you can specify the type of curve to be automatically placed at every point of intersection between tangents now in the curve and spiral settings dialog box specify the following parameters we’ll leave the type at its default the spiral in checkbox we’re going to leave that cleared curve we’re going to leave it at selected but for the default radius let’s change that to 350. and we’re going to leave the spiral out check box cleared click ok now under your layout tools go ahead and click that drop down again select tangent to tangent with curves snap to the center of circle a go ahead and stretch the line out to B then continue until you get to D
and go ahead and right click to end the command go ahead and pan and zoom to review the style you can see all of the stations are on their own layer
we can see our tangency
and it looks very very nice now as you’re examining your alignment note the geometry points for the start and the end of each line spiral and curve so that’s how you go about creating an alignment with the alignment layouts tools toolbar in civil 3D in this exercise you’ll add a free curve and a free spiral curve spiral to a simple alignment the drawing contains a simple alignment as you can see here consisting of three tangents in the next few steps you’ll add three curves at circles B and C this exercise continues from the previous exercise where we created an alignment from the alignment layout tools toolbar go ahead and open up the Align Dash 2 drawing in your tutorials folder I’ll set your drawing window so that you can see both circles B and C on the surface if the alignment layout tools toolbar is not open select the alignment
right click and select edit alignment geometry
in the toolbar go ahead and select this drop down menu and then select free curve fill it between two entities using a radius now the command line is asking us to select the first entity go ahead and select the tangent that enters into Circle B then select the tangent that exits from Circle B press enter to select the default value of a curve less than 180 degrees now enter a radius value of 200.
now you can see the curve is drawn between the two tangents as specified go ahead and exit out of your command and zoom into Circle C now select this drop down menu
and select free spiral curve spiral between two entities
it’s asking us for our first entity select the tangent that enters into Circle C then pick the tangent that exits Circle C go ahead and press enter to select the default value of a curve less than 180 degrees and then enter a radius value of 200
enter a spiral in length of 50 and then enter a spiral out length of 50. now note that notice the default values that are shown on the command line as you can see right here go ahead and exit the layout command by right-clicking in the drawing area I’ll go ahead and zoom out and as you can see this is how we go about adding free curves and spirals to an alignment in civil 3D in this exercise you’ll add two floating curve entities to a simple alignment first you’ll add a best fit floating curve that follows the most likely path through a series of points then you’ll add a floating reverse curve with spirals now the drawing shows a simple alignment consisting of three tangents with curves in the next few steps you’ll add two floating curves to the end of the alignment this exercise continues from our last exercise where we went about adding three curves and spirals to an alignment now note that this exercise uses the Align Dash 2 drawing with the modifications you made in the previous exercise or you can open the alignment 3 drawing from the tutorials folder now go ahead and pan and zoom until you see circles d and e on the surface on the Home tab go ahead and go into your layer management
and then turn on your C Dash points layer
now you’ll see a group of points are displayed you’ll use these points as a basis for creating a floating curve that follows the most likely path through these points now note that if these points do not appear go ahead and type in regen on the command line we’ll do that right now
if the alignment layout tools toolbar isn’t open select the alignment
remember that we can right click on the alignment
and click edit alignment geometry we get our toolbar now select this drop down menu pick the floating curve best fit then you’re prompted on a command line to select the entity to attach to go ahead and select the tangent that ends in Circle D
then in the curve by Best Fit dialog box make sure that the cocoa points is selected so we have that selected right here go ahead and click ok now the command line prompts you to select Point objects or numbers and groups go ahead and enter in G for groups
now in the point groups dialog box select all points then click ok the regression data Vista displays information about each of the points that are included in the regression analysis let’s move this off to the side a little bit now the drawing displays a red dashed line indicating the path of the best fit curve and x marks the location of each regression data point let’s open the regression data up just a little bit more
now note the point numbers in the point number column right here are sequentially generated as regression data points are added or removed they do not correspond to the actual Autodesk civil 3D Point numbers now you’ll modify some of the regression data to better suit your design and the regression data Vista go ahead and browse to point 16.
select the pass-through check box selecting this checkbox specifies that if the curve does not deviate from the regression data it will always pass through point 16. now go ahead and click the check box to create the best fit floating curve the regression data Vista closes and the regression Point markers disappear now in the drawing select your alignment click the cyan grip at Point 16 which is the end of the floating curve drag it towards one of the other points click to place the grip at its new location in the toolbar click edit best fit data for all entities
now notice that the original regression data is replaced in the regression data Vista and the original best fit curve is displayed in the drawing The Shield icon up at the top here indicates that the alignment layout does not comply with the regression data when you move the grip at Point 16 you move the pass-through point from the location you specified earlier click the shield to synchronize check to close the Vista now you can see that the entity returns to its original location go to your home tab
and then enter your layer management
and then turn off your C points layer
on your layout toolbar click this drop down select the floating reverse curve with spirals from curve radius through point our command line says select curve to attach to select the curve entity that ends in circle e enter a spiral length of 75
a radius of 200 and a spiral out length of 75. now specify a pass-through Point through the center of f
the reverse curve with spirals appears exit the layout command by right-clicking in the drawing now you know how to go about adding floating curves to an alignment in civil 3D in this exercise you’ll use the alignment entities Vista and Alignment layout parameters dialog box to edit the layout parameter values of an alignment this exercise continues from the creating alignments tutorial note ensure the dynamic input is turned on the way you go about doing that is just type in d y n and make sure it’s set to 1. which it currently is so press enter this drawing uses the align-4 drawing in your tutorials folder the drawing contains a surface marked with several circles as you can see here labeled a through f note ensure that object snap or o snap is turned on you do that by clicking on this button right here if the alignment layout tools toolbar isn’t open go ahead and select your alignment then in the modify panel click on Geometry editor
on the alignment layout tools toolbar click the alignment grid View
you can go ahead and examine the alignment entities table in Panorama in the first column you’ll see that the alignment segments are numbered in the order in which they’re solved each row of the table shows useful design data about a specific entity each curve group has a two-part entity number and a separate table row for each spiral and curve values shown in Black can be edited note to make other parameters available for edit you can change the tangency constraint by clicking on it and you get a drop down window or you can change the parameter constraint just click this little lock icon on the alignment layout tools toolbar click the sub entity editor
now as you can see right here the layout parameters window is displayed but it contains no data go ahead and select the grid view button again and then select any row for Segment number four which is the free spiral curve spiral entity in Circle C in your drawing window the design data for all three of these sub entities is displayed in a two column table in the alignment layout parameters window where the data is easy to review and edit if your design requires precise values for minimum curve radius length or spiral a values you can use the alignment layout parameters window to enter the values in this window let’s go ahead and change the length value for a spiral to a higher number
such as 100
note how this immediately increases the spiral length in three locations in both the alignment layout parameters window and in the alignment entities table if we close all this out
numeric values change and the geometry points move along with their station values and the length of the Spiral itself changes let’s go about displaying a range of sub entities in the alignment entities Vista in the drawing ctrl-click the curve entity for Circle B
the alignment entities Vista displays only the attributes for the curve entity in the drawing control click the spiral curve spiral entity in Circle C
notice that the alignment entities Vista now displays the attributes for each of the entities you selected plus the tangent between them to display the parameters of another entity in the alignment layout parameters dialog box press escape to display all alignment entities on the alignment entities Vista so that’s how you go about editing the layout parameter values of an alignment in civil 3D in this exercise you’ll use grips to move alignment curves in future lessons you’ll learn how to grip edit offset and curb return alignments in the working with alignment and curb return alignments tutorial note to change the behavior of an entity you can change the tangency constraint and parameter constraint value this exercise continues from editing the layout parameter values of an alignment note ensure that the dynamic input is turned on you can do that by typing in d y n
and make sure it’s set to 1. and make sure that the osnap is turned off which is this icon right here this is the on position and this is the off position let’s go ahead and grip edit a free curve entity note this exercise uses the Align Dash 4 drawing with the modifications you made from the previous exercise zoom in to Circle B
ick the alignment
and grips appear at the curve ends midpoint and at the point of intersection or pi go ahead and click the midpoint grip until it turns red click a new location for the curve to pass through
notice that the curves and tangents remain tangent to each other but both endpoints move along the tangents click the radius grip which is this Arrow right here go ahead and experiment by moving it
notice that this grip affects only the curve radius and constrain to the direction of the radius change next select either an endpoint grip or the pi grip I’m going to select the pi grip experiment with reshaping the curve in different ways let’s grip edit a floating curve entity pan around to this area within circles d e and f
fit them in my screen just like so select the alignment and then select the grip within Circle D notice how it turns red now notice that there’s a pass-through point which is kind of a circular grip right in the center of circle f and notice that it doesn’t move it stays right in the center of circle f go ahead and click any location now select this pass-through Point within circle e see how it turns red click a new location for the grip notice that the pass-through Point within Circle D doesn’t move select a new location
the spiral curve entity in Circle D moves along the preceding tangent to accommodate the new pass-through point
and the labels and tables panel click the drop down for add labels then select single segment click the curve within Circle D
a label is placed on the Curve press enter to end the label command click the curve to activate the grips and edit the curve using the pass-through point
I’m going to select this location right here and escape to deselect the alignment now the label shows the new length of the Curve so that’s how you go about grip editing and Alignment in civil 3D in this exercise you’ll hide a portion of an alignment from View when you apply a mask to a portion of an alignment the alignment sub entities labels and marker points are not drawn but these items still exist but are hidden from View this feature is useful for working on an intersection in many cases you don’t need to see the alignment geometry that passes through the intersection in this exercise you’ll mask the portion of an offset alignment that passes through an intersection this exercise continues from grip editing and alignment go ahead and open up your align Dash 5 drawing which is located in your tutorials folder you’ll see that the drawing contains a four-way intersection
notice that the offset alignments along Road a are not displayed in the intersection area each of these alignments has a mask applied to the region that passes through the intersection in the following steps you’ll apply a mask to the offset alignments along row b select the offset alignment on the north side of row b then within the offset alignments tab go into alignment properties
in the alignment properties tab select masking on the masking tab click this button right here for add masking region
in the drawing select the end point of the Northwest curve
this curb return is going to specify the start point of the Mast region select the endpoint of the Northeast curb return
this is going to specify the endpoint of the mass region and the alignment properties dialog box go ahead and select apply the mask is applied to the specified region we’ll go ahead and do the same thing for the south side of road B
select alignment properties and masking click this button right here select the endpoint of this curb return and then go to the end point of this curb return
click apply then ok so that’s how you go about applying a mask to an alignment in civil 3D
