In this exercise you’ll create a three-way intersection and generate a corridor that maintains the crowns of both roads to create a complete intersection model you must have a center line alignment and profile for each of the intersecting roads the horizontal and vertical geometry for the remaining elements including the offsets and curb returns is generated based on the parameters you specify in a pure Road intersection the crowns of all intersecting roads are held at a common grade the pavement for both roads is Blended into the curb return regions which form the transitions between the intersecting roads the drawing for this exercise contains a corridor along each of the intersecting roads each Corridor is made up of a corridor assembly and a Center Line alignment and profile so let’s specify the intersection location go ahead and open up your intersection Dash create dash one drawing in your tutorials folder then go ahead and go into your home tab and then into your create design panel click the intersections drop down and select create intersection now our command line is asking us to select an intersection point we’re going to select this point right here between our two roads now this is an intersection point of the two alignments
now we’re going to be specifying the corridor grade parameters we’re currently in the create intersection wizard and we’re on the general page go into your intersection Corridor type click the drop down and we want to select all crowns maintained you’ll see in the graphic how that’s going to be generated go ahead and click next now we’re going to specify the geometry of the offsets and curb returns and the geometry Details page click offset parameters
now note that the default parameters are stored in the drawing settings you can modify the default parameters during the intersection creation process now in the offset parameters dialog box specify the following parameters under the secondary Road we’re going to specify a left offset alignment definition
and that offset value is going to be 3.5
now let’s look at the right
go ahead and change that to 3.5
now in this checkbox right here under create new offsets from start to end of center lines we’re going to leave that checkbox cleared for right now although when this option is selected offset alignments are created along the entire length of the center line alignment this option is useful when you need to use offset alignments and profiles as targets for other objects including other intersections along the same road go ahead and click ok
now we’re back onto the details page now the next step is is to select this curb return parameters
in the intersection curb return dialog box under curb return parameters specify the following parameters for the curb return type we’re going to leave its defaults at circular fillet but for the radius we’re going to change that to 7.5 now note that in the drawing
temporary graphics highlight the currently selected curb return go ahead and right click on the curb return parameters we’re going to click to copy these to all quadrants this command copies the curb return parameters to all intersection curb return regions the number of curb return regions is automatically generated based on the existing horizontal geometry for example if this was a four-way intersection four curb return regions would be available now go ahead and click ok so now we’re back to the intersection wizard let’s focus our attention on offset and curve return profiles in this region right here make sure that this checkbox is selected to create offset and curb return profiles to produce a complete Corridor model of the intersection it’s necessary to create profiles for the offset alignments and curb return alignments for this exercise you’ll accept the default offset and curb return profile settings so go ahead and click next let’s specify the corridor parameters and the corridor regions page specify the following options make sure that the checkbox for create corridors in the intersection area is checked off we want to add to an existing corridor and make sure that Second Street is selected for the surface to Daylight 2 we’re going to leave it on the existing grade now we’re going to select an assembly set to import go ahead and choose browse go ahead and navigate to your tutorials folder then go to this XML file intersection assembly set all crowns.xml select that and click open an assembly set enables you to quickly import a group of existing Corridor assemblies and then apply them to specific section types now let’s go ahead and create our intersection
the intersection is created in new Corridor regions are created in the intersection area as you can see right here let’s examine the new objects in the tool space under the prospector go ahead and look at your alignments go ahead and expand that expand your Center Line your offset alignments and curb return alignments we’ll open up our tool space just a little bit more to see everything
at the beginning of this exercise only Center Line alignments existed the offset alignments and curb return alignments were created using the parameters that you specified in the create intersection wizard note in the drawing the offset alignments and station labels are blue and the curb return alignments are red
under the offset alignments the go ahead and expand the First Street left offset alignment next expand the profiles collection layout profiles for the offset alignments and curb return alignments were created using the parameters that you specified in the create intersection wizard let’s go about closing these gaps in our Corridor for Second Street in the drawing select the corridor in the intersection area
you’ll see that we have grip sliders at the start and end of our Corridor regions
click the Second Street corridor
you’ll see a grip at station zero four zero go ahead and select that grip notice how it turns red now in the command line type in 21.
we’ve now closed the gap between the Second Street Corridor and our intersection next let’s go ahead and fill in this Gap right here go ahead and Escape out of the command select the Second Street corridor and now select copy region
select the portion of the corridor that loops around the site
now the command line is asking us to specify the start region station or fill we want to choose fill
now we have to specify the region location
if we hover over our Gap you’ll see a red line that appears showing that this is the gap that’s going to be filled go ahead and click that area
so now the Gap is filled go ahead and press enter to exit the command let’s rebuild all of our corridors
the Second Street Corridor rebuilds eliminating the gaps now let’s select the first street corridor
we want to eliminate this gap between our two corridors right here go ahead and select our grip notice how it turns red and then slide it to the beginning of our intersection which is right about here
so that’s how you go about creating a Peer Road intersection in civil 3D in this exercise you’ll create an intersection with entry and exit turn Lanes at the primary Road the secondary Road Crown will blend into the primary Road edge of pavement you can use the workflow that’s demonstrated in this exercise to create an intersection with any combination of turn lanes and curb returns let’s specify the intersection location and primary Road go ahead and open up your intersection Dash create-2 drawing in your tutorials folder go ahead and go to your home tab and then to your create design panel next go to your intersections drop down and select create intersection
the command line is now asking us to select an intersection point go ahead and select this one right here the intersection point of Road a and Road B alignments click Road a to specify it as the primary Road specify the corridor grade parameters in the create intersection wizard on the general page under intersection Corridor type we want to make sure that it stays on its default of primary Road Crown maintained go ahead and click next now we’re going to specify the horizontal and vertical geometry parameters on a geometry Details page click offset parameters
default horizontal and vertical geometry parameters are stored in the drawing settings you can modify the default parameters during the intersection creation process and the offset parameters dialog box specify the following parameters under primary Road left offset alignment definition select the offset value
we’re going to change this to 6. now go to the right offset value we’re going to change that to 6 as well now under the secondary Road we have a left offset value of three we’re going to leave that as it is the same goes for the right offset value we’re going to leave that at three now click ok
on the geometry Details page click curb return parameters the default parameters for the first intersection quadrant are displayed in the intersection curb return parameters dialog box in the drawing if we move this to the side the first quadrant is highlighted arrows indicate the direction of incoming and outgoing traffic
in the intersection curb return dialog box select widen turn lane for outgoing Road the whitening details at outgoing Lane parameter collection is displayed in the property tree when you highlight a property the preview graphic at the bottom of the dialog box updates to illustrate the property in a typical intersection examine the default values that have been specified for this drawing but do not change any of them go ahead and click next for the southeast quadrant select widened turn lane for incoming Road then click next for the Southwest quadrant select widened turn lane for outgoing Road then click next for the Northwest Quadrant select widen turn lane for incoming Road
now we’re going to click ok
and the create intersection wizard make sure the checkbox for create offset and curb return profiles is selected then click next lastly let’s specify the corridor parameters on the corridor regions page specify the following options we’re going to go ahead and create corridors in an intersection area and we’re going to create a new corridor now this new corridor will have a daylighted surface to our existing ground and then we want to select an assembly set to import go ahead and click browse now within your tutorials folder you have an assemblies folder and then metric and under the metric folder we have Autodesk metricassembly sets dot XML go ahead and select that and click open then Focus your attention on the maintain priority Road crown under curb return fillets select this button right here now this dialog box is asking us to select an assembly you can use the select assembly dialog box to substitute an assembly with another assembly that is in the current drawing to save your changes as a new assembly set click save as set on the corridor regions page for this exercise you’ll accept the default assembly set go ahead and create intersection the intersection is created and new Corridor regions are created in the intersection area notice that the curb returns have widening regions to allow traffic to exit from and merge onto Road a so that’s how you go about creating a primary Road intersection with turn Lanes in this exercise you’ll use the existing offset alignments and profiles of the primary road to create an intersection and then add the new intersection to the existing primary Road Corridor the workflow that’s demonstrated in this exercise is useful when you need to create several intersections along a single corridor you define the offset geometry for the primary Road and then reuse it for subsequent intersections let’s start by specifying the intersection location and primary Road go ahead and open up your intersection Dash create-3 drawing in your tutorials folder now this drawing contains an intersection of two alignments row a and Road C offset alignments exist on either side of road a and there is an existing intersection north of Road C go ahead and go to your home tab and then to your create design panel click on the intersections drop down and select create intersection in the drawing our command line is asking us to select an intersection point go ahead and select the intersection of Road a and Road C next our command line is asking us to select a main road alignment or press enter to select from a list click the road a alignment to specify it as the primary Road now let’s specify the corridor grade parameters in the create intersection wizard on the general page under the corridor type
make sure that the primary Road Crown is maintained
go ahead and click next now we’re going to specify the horizontal geometry parameters on the geometry Details page click the offset parameters and the offset parameters dialog box under the primary Road let’s look at the left offset definition we do want to use the existing alignment so switch that to yes
for the alignment name go ahead and press this button right here now we’re going to actually pick this alignment in the drawing select the offset alignment on the left hand side of the road a alignment go ahead and click ok in the intersection offset parameters dialog box let’s take a look at the right side we’re going to use an existing alignment
we’re going to choose our alignment and we’re going to pick it in our drawing again now pick the right side of row a
go ahead and click ok and then click ok
now select curb return parameters the default parameters for the first intersection quadrant are displayed in the intersection curve return parameters dialog box in the drawing the first quadrant is already highlighted with arrows Associated to indicate the direction of incoming and outgoing traffic we’re going to start with the southeast quadrant
make sure that the widened turn lane for incoming road checkbox is selected now select the Northwest Quadrant
we’re going to do the same thing we’re going to make sure that this checkbox is checked for the incoming Road now click ok
now let’s specify the vertical geometry parameters on the geometry Details page under offset and curb return profiles select Lane slope parameters now within the intersection Lane slope parameters dialog box specify the following options under the primary road for the left edge profile definition we are going to use an existing profile and to choose that profile we select that button right there and then we’re going to select Road a two percent click ok then we’re going to repeat this for the right side
but for the profile name we’re going to select Road a two percent one
click ok and then click ok lastly we’re going to specify the corridor parameters go ahead and click next and now we’re on the corridor regions page let’s specify the following options go ahead and check off create corridors in intersection area but we’re going to add to an existing corridor we’re going to add it to Corridor one
and we’re going to Daylight to the existing ground surface under the select assembly set to import let’s go ahead and click browse and navigate to your metric assembly sets select the metricassembly sets dot XML and click open
now go ahead and create intersection and there you have it that’s how you go about creating an intersection with existing geometry in civil 3D
