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Hi all,
Some days ago I created a short video how to get data from an old drawing (attribute data) in to a ASCII-file to be used as Survey input.
The customer wanted to be able to use the new Survey import functionality in AutoCAD Civil 3D and set up a Survey database. They also wanted to get the same look and feel with symbols and styles on their data.
This video shows how to extract the old data using Map Query.
// Ove
After having some great events in Ireland with our users we are this time going around the country to give our users a more local event.
The user groups are in November.
See you there
Jack Strongitharm
I don't think I am on my own when I say that when it comes to something new, be it software, gadgets etc we don't read the instructions.
Subassemblies are a bit like this as they are from very simple to extremely complex to what they can achieve and is really one of the huge strengths of Civil 3D as they can do the maths, what if etc as they are calculated down the length of your alignment.
However, do you know what your line/link and shapes codes are?
Probably not.
Well if you have read the instructions would you probably know.
On any of the subassemblies in the tool palette you can right click and get help and or in the subassembly properties there is a link to the help.
As you can see there is a little diagram and a list to each of the codes that is created.
Want to see them on the drawing?
Here we go
Assemblies are used and drawn using code set styles.
These we can apply to the assembly creation, plan and section drawings.
So you can have different styles ready to switch on anytime.
In my UKIE template I have such styles.
However, how about applying the subassembly codes on the drawing.
Click on the assembly and properties and go to the code tab.
You can do this with an existing style or we can make a new one.
We could apply them here in the default and no codes section, but there will be cases of the 'Top' and 'Datum' link codes which will overlap the individual codes. So I want to turn those off
Using the 'Import Codes' you can select either your assembly or corridor to fill up the list with what codes are used.
As you can see above a label style can be made to apply the code to points, links and shapes.
(A separate style for each of these types will be needed)
Here is the result, coloured up also so I know which is point/link and shape
Jack Strongitharm
Farely unknown little setting so thought I would raise it.
When creating especially datum/formation surfaces you want the surface to hug the bottom of the corridor assemby.
So sometimes you may get this result.
So to change it, go to the corridor properties and the surface tab, or in 2011 click on the corridor and hit surfaces from the ribbon (oh yes very cool!)
Add bottom links to your datum/formation surface
And here we go all sorted and will stay this way from this point
Jack Strongitharm
Ok, this is turning into a brain dump week
So to do this little technique we merely use a cut and fill method to find out where a given level would intersect the ground.
Step 1
Draw a rectangle over your surface
Step 2
Convert the rectangle to a feature line and assign it a constant level/elevation of what you require to check against
Step 3
Create a surface from this rectangle
Step 4
Create a volume tin surface comparing the ground to this flat surface
Step 5
Create a style which just shows a user contour only and set the layer, colour, lineweight etc and apply this to your volume surface
Step 6
Click on the volume surface and its properties and click on the analysis tab
Choose user contour, set one range and enter the value 0
Click Apply
Step 7
The line drawn is where the flood level intersects the ground surface
Step 8 - Change
So by turning on the rebuild automatic to your flood level surface and the volume surface, you can now select your featureline and adjust its level/elevation and watch how the flood extents take affect.
Fun, or scary depending if you live near the area affected!
Step 8 - Visualisation
Of course its nice to have a pretty picture of your work, so all we need to do now is restrict the flood surface to the contour line being drawn.
This you will need to extract the contour line from the volume surface, so select the volume surface contour line, extract objects and ok to the contour line.
Add this polyline to your flood level surface as a non destructive outer boundary.
(NOTE you may need to close the boundary like mine as the 0 level went outside my surface limits.)
Then using the techniques explained in my earlier post on boundaries and holes you can create a copy of your ground to cut a hole out of. Link to post
This will put your volume surface out of date also as you are affecting the surface it is based on, again make a copy of it if you prefer with the paste edit option.
Then of course set render materials to suit
Jack Strongitharm
Its like catching a bus sometimes, you wait for one and three come at the same time!
Anyway, carrying on from the last two tips this week, lets look on how to use those boundaries for grading tasks also.
I find a lot that users are wanting to use corridors to form ditches and other features at the side of their roads and other formations they are designing and over complicating the task by try to use corridors for everything.
I quite often will use a corridor to create a surface or linework to do the maths and then butcher it to suit my purposes.
So in this airport case I just wanted to grade from the runways and taxiways down to form a basic basin.
With the corridors crossing with junctions etc, the best way is to simply use the inner surface boundary of the pavements and grade from them.
Obviously the boundary is static, but easy enough to do an update if you need.
So I first recommend carrying out a weed on the boundary, with us forming the boundary in an unconventional way.
This you find in the modify tab and feature lines. (You can use this command on polylines also)
Then using either the Civil 3D grading or in my case just the 3D stepped offset to create an offset of a distance and slope
Stepped Offset is again in the modify tab and feature lines.
This is the only way to offset 3d polylines in AutoCAD, i,e, not in standard AutoCAD.
Then just create your surface from breaklines and you are done
Jack Strongitharm
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