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Section View for Intersection design

7 REPLIES 7
Reply
Message 1 of 8
wendyllc
699 Views, 7 Replies

Section View for Intersection design

How can I view the cross-section of multiple alignments that form the intersection road design?
I can only select one alignment at a time.
The section view does not seem to be updated when I make changes to my sub-assembly.
7 REPLIES 7
Message 2 of 8
Anonymous
in reply to: wendyllc

Hi wendyllc,

As I understand it as far as C3D2005 goes, here is a brief overview (some of
which you clearly know). When you create section sample lines for the first
time, you also create a "sample line group" to which they will belong. Each
sample line group must be related to a single alingmnet (I think for lots of
reasons, stationing among them)---notice that in prospector, the sample line
groups are deeply embedded in the alignment branches of the tree. Those
alignments correspond to baselines in the corridor model.

When you create a sample line group, you have to choose which surfaces to
cut sections through---including the existing ground surface, the corridor
model itself, and any surfaces that you've created and exported as TINS from
the corridor model. When you create a section view, it comes from a sample
line and has the sample line group properties that the chosen sample line
belongs to. So if you just chose the existing ground and the corridor model
to cut the sections through, that's all you will see in a section view for
sections of that section line group; if you included corridor surfaces, you
will see those, too; and if you chose just the existing ground and corridor
surfaces (not the corridor model itself), that's what you will see in the
section view.

So let's say you have a corridor model with your intersection (done by using
the techniques that Chakri and Dan illustrated in their webcasts). Further,
you have created corridor surfaces for all of the relevant components in the
corridor (e.g., top, pave1, pave2, base, subbase, datum, etc.). Now, you
create section views along one of the centreline alignments through the
intersection. If you sampled the existing ground surface, you will see that
in your section views. If you sampled the corridor model, you WILL NOT see
the corridor in your section views because the extent of the centreline
alignment through the intersection wasn't used as a baseline region in the
construction of the corridor model. However, if you sampled the corridor
surfaces when you created the sample line group, you WILL see those in your
section view (for the same reasons that you see your existing ground surface
across the width of your section view---they are just surfaces, now
disengaged from the corridor model).

By the way, if you make changes to your assemblies and rebuild your
corridor, you will have to re-export the corridor surfaces to have the
changes reflected in your corridor surface TINS, and hence in your section
views that sample those TINS.

It might be nice to be able to show the WHOLE corridor in any section view
regardless of chosen alignments/baseline regions---without having to create
and export corridor surfaces. Other people might have thoughts about this.

To show changes to your sections in your section views, resulting from
alterations in your corridor (changed assemblies, for example), you must
resample for the section line group in question. You can do this either by
using the prospector or by selecting a sample line of the group you want to
resample, and choosing "Sample Line Group Proprties" in the right-click
context menu. If you've merely rebuilt the corridor wth assembly changes,
and you want to keep everthing else the same, just hit the resample button.
Your section views will update. Note that in the "Sample Line Group
Properties" dialog, you can also choose to change the data objects that you
sample.

Again, I should say that this is how it works in C3D2005. I haven't had
enough time to check out C3D2006 toroughly, yet. It would be nice for
someone else to mention how changes in C3D2006 affect this process. Also if
I've made any errors or omissions, I am happy to be corrected and informed!

Hope this helps to clarify these things for you.

--- Evan


wrote in message news:4845305@discussion.autodesk.com...
How can I view the cross-section of multiple alignments that form the
intersection road design?
I can only select one alignment at a time.
The section view does not seem to be updated when I make changes to my
sub-assembly.
Message 3 of 8
wendyllc
in reply to: wendyllc

Thanks Evan for the prompt reply!
I understand where you are coming from. However, the section view at the intersection point only contain one side of the assembly associated with that particular alignment which correspond to the baseline.
It would be nice as you have mentioned earlier to be able to view the whole cross-section for the corridor model.
Message 4 of 8
Anonymous
in reply to: wendyllc

Hiya,

I'm wondering what advantage having the corridor model showing in one's
section views might have over the surfaces generated from the corridor
model. It's true that one could see the point, link, and shape codes; but
for plots, I just want to show the data that the surfaces provide.

I suppose that there could be possible (or doubtful) efficiency gains: being
able to see sections of the entire corridor would allow one to tweak the
design to some extent before going through the process of creating and
exporting corridor surfaces. Any thoughts on why it might otherwise be
useful to use the corridor model in section views?

Cheers,

--- Evan

wrote in message news:4845477@discussion.autodesk.com...
Thanks Evan for the prompt reply!
I understand where you are coming from. However, the section view at the
intersection point only contain one side of the assembly associated with
that particular alignment which correspond to the baseline.
It would be nice as you have mentioned earlier to be able to view the whole
cross-section for the corridor model.
Message 5 of 8
wendyllc
in reply to: wendyllc

Hi Evan!
Good question from you! I am from Malaysia and as far as I am concern, once I have my road design finalized, it is crucial and important that the construction drawings for horizontal alignment, vertical alignment, cross-section (SECTION VIEW) at a specific station be plotted out. I see the advantage and the time saved by using Civil 3D in my design. However, if I am not able to see the whole cross-section as per design, then I don't think it is practical because the reason I use Civil 3D is that I can do design as well as extract my construction drawings from there. Can it be done?
Cheers,
wen
Message 6 of 8
Anonymous
in reply to: wendyllc

One example:

A railyard. We would like to see the rails for each baseline, but it's
impossible to build a surface which shows the rails.

Drew Burgasser
CAD Masters, Inc.


"Evan Williams" wrote in message
news:4845774@discussion.autodesk.com...
Hiya,

I'm wondering what advantage having the corridor model showing in one's
section views might have over the surfaces generated from the corridor
model. It's true that one could see the point, link, and shape codes; but
for plots, I just want to show the data that the surfaces provide.

I suppose that there could be possible (or doubtful) efficiency gains: being
able to see sections of the entire corridor would allow one to tweak the
design to some extent before going through the process of creating and
exporting corridor surfaces. Any thoughts on why it might otherwise be
useful to use the corridor model in section views?

Cheers,

--- Evan

wrote in message news:4845477@discussion.autodesk.com...
Thanks Evan for the prompt reply!
I understand where you are coming from. However, the section view at the
intersection point only contain one side of the assembly associated with
that particular alignment which correspond to the baseline.
It would be nice as you have mentioned earlier to be able to view the whole
cross-section for the corridor model.
Message 7 of 8
Anonymous
in reply to: wendyllc

What a fantastic explanation! I wholeheartedly agree that it would be VERY
nice to be able to sample other corridors in my sections views. Many times
I have adjacent roads on a steep hill and I'd like to see where the other
road is in my sections without necessarily having to create a corridor
surface. Sometimes these corridor surfaces' boundaries don't behave and you
get a strange thing going on. The corridors almost always look great, but
it sometime takes a little time to get the surface just right. This would
be a huge time saver over the life of a project.


Well said, Evan,
Matt Kolberg


"Evan Williams" wrote in message
news:4845353@discussion.autodesk.com...
Hi wendyllc,

As I understand it as far as C3D2005 goes, here is a brief overview (some of
which you clearly know). When you create section sample lines for the first
time, you also create a "sample line group" to which they will belong. Each
sample line group must be related to a single alingmnet (I think for lots of
reasons, stationing among them)---notice that in prospector, the sample line
groups are deeply embedded in the alignment branches of the tree. Those
alignments correspond to baselines in the corridor model.

When you create a sample line group, you have to choose which surfaces to
cut sections through---including the existing ground surface, the corridor
model itself, and any surfaces that you've created and exported as TINS from
the corridor model. When you create a section view, it comes from a sample
line and has the sample line group properties that the chosen sample line
belongs to. So if you just chose the existing ground and the corridor model
to cut the sections through, that's all you will see in a section view for
sections of that section line group; if you included corridor surfaces, you
will see those, too; and if you chose just the existing ground and corridor
surfaces (not the corridor model itself), that's what you will see in the
section view.

So let's say you have a corridor model with your intersection (done by using
the techniques that Chakri and Dan illustrated in their webcasts). Further,
you have created corridor surfaces for all of the relevant components in the
corridor (e.g., top, pave1, pave2, base, subbase, datum, etc.). Now, you
create section views along one of the centreline alignments through the
intersection. If you sampled the existing ground surface, you will see that
in your section views. If you sampled the corridor model, you WILL NOT see
the corridor in your section views because the extent of the centreline
alignment through the intersection wasn't used as a baseline region in the
construction of the corridor model. However, if you sampled the corridor
surfaces when you created the sample line group, you WILL see those in your
section view (for the same reasons that you see your existing ground surface
across the width of your section view---they are just surfaces, now
disengaged from the corridor model).

By the way, if you make changes to your assemblies and rebuild your
corridor, you will have to re-export the corridor surfaces to have the
changes reflected in your corridor surface TINS, and hence in your section
views that sample those TINS.

It might be nice to be able to show the WHOLE corridor in any section view
regardless of chosen alignments/baseline regions---without having to create
and export corridor surfaces. Other people might have thoughts about this.

To show changes to your sections in your section views, resulting from
alterations in your corridor (changed assemblies, for example), you must
resample for the section line group in question. You can do this either by
using the prospector or by selecting a sample line of the group you want to
resample, and choosing "Sample Line Group Proprties" in the right-click
context menu. If you've merely rebuilt the corridor wth assembly changes,
and you want to keep everthing else the same, just hit the resample button.
Your section views will update. Note that in the "Sample Line Group
Properties" dialog, you can also choose to change the data objects that you
sample.

Again, I should say that this is how it works in C3D2005. I haven't had
enough time to check out C3D2006 toroughly, yet. It would be nice for
someone else to mention how changes in C3D2006 affect this process. Also if
I've made any errors or omissions, I am happy to be corrected and informed!

Hope this helps to clarify these things for you.

--- Evan


wrote in message news:4845305@discussion.autodesk.com...
How can I view the cross-section of multiple alignments that form the
intersection road design?
I can only select one alignment at a time.
The section view does not seem to be updated when I make changes to my
sub-assembly.
Message 8 of 8
Anonymous
in reply to: wendyllc

Hey, thanks, Matt.

Regarding corridor surface boundaries, I'd be really interested in hearing
any observations from you about the best ways to make this work. I'm not
sure whether you checked out the thread "Baselines in corridor surface
boundaries" (2005-05-04); if not check it out. I did send a couple of
drawings to Dan and Chakri last week, and Chakri appears to be finding some
fixable problems with the program---service pack material, unfortunately.
However, since the corridor surface boundary routine works inconsistently
currently, any info from anyone on how to best make it work would be most
welcome---especially in the context of intersections and cul de sacs.

Regarding the "look" of corridors, I have mixed responses---especially in
cross sections. It's fairly straight forward to change the look of the
various parts of the model, once one takes the considerable time to dig
deeply into the toolspace "multipurpose styles" settings; but there are some
surprising and totally undocumented (as far as I can see) anomalies.

Take the ShoulderVerticalSubbase subassembly, for example. I started a
thread (2005-05-16) on one strange aspect of this one, having to do with
unexplained "alter-ego" parameters. Nobody's responded to that thread, yet.
Someone from Autodesk might be kind enough to say something.......please!
But another couple of strange things include the following.

Let's say we've made an assembly with the LaneInsideSuper subassembly and
we've inserted the ShoulderVerticalSubbase subassembly to it (throw in
whatever daylighting you want). Zoom in, and follow the vertical line from
the attachment point down to the bottom of the two subassemblies. Note that
they diverge. Not by much, but it makes me wonder why.

Also when I see the ShoulderVerticalSubbase subassembly in a cross section,
diagonal lines (they look like link lines) are drawn across the shape spaces
for the subassembly from inside top to outside bottom. The shape code
hatching is split and drawn only in the upper half of that shape space---as
in the attached image. Is this deliberate? Is it controlable? Is it
documented somewhere? How does it affect corridor surface generation and
volume calculation? Are those diagonal lines "links" of some kind?

Lots of questions and concerns!

--- Evan



"Matt Kolberg" wrote in message
news:4849958@discussion.autodesk.com...
What a fantastic explanation! I wholeheartedly agree that it would be VERY
nice to be able to sample other corridors in my sections views. Many times
I have adjacent roads on a steep hill and I'd like to see where the other
road is in my sections without necessarily having to create a corridor
surface. Sometimes these corridor surfaces' boundaries don't behave and you
get a strange thing going on. The corridors almost always look great, but
it sometime takes a little time to get the surface just right. This would
be a huge time saver over the life of a project.


Well said, Evan,
Matt Kolberg

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