Jump to content
zabilya

topographic map in 3d for dummies

Recommended Posts

zabilya

Thanks a lot

I dont want to torture you with this thing

 

I drew a sketch of what i wish to obtaine

 

Do you think its possible at all?

Do u think its an efficient way of calculating cut and fill?

 

Its more of a civil technician task

 

My thinking is that once you have the chunk of earth leveled, you can calculate the excavation for foundation, draw the foundation in the excavated area, calculate the volume of concrete, calculate the backfill....

 

Any comments are welcome

sketch.jpg

Share this post


Link to post
Share on other sites
shift1313

Well from the contour lines you posted i think it would work because its a very small elevation change. The issue you will run into is while you do have elevation lines, the approximation of the land isnt perfect. For instance if one of your lines was at 99' and the land dropped suddenly but but not an entire foot until the next contour line, you are not going to know this and it wont be well represented in the model.

 

This certainly isnt my area so i am really not sure what to tell you on if it will be accurate enough or not. Maybe someone who does this type of work will chime in.

 

 

On the dwg you posted(thanks for putting your stuff on different layers by the way:)) how did you create those contour lines?

 

 

I was just messing with your drawing again and i found one of the issues. The second line(at 99ft) overlaps itself which is where one of the errors was coming from. I uploaded a screen shot of it below.

Topohelp3.jpg

Share this post


Link to post
Share on other sites
shift1313

after you fix that second line, the loft works fine so this was the only issue. I just grabbed the control points(blue) and snapped them to the intersection to straighten out that one curve.

 

Use you LOFT by selecting the curves in order and get a surface model of the land. Using the closed surface option on the loft window is not a good option in this case. If you wish to have a solid model(which i think is what you need) you will have to add some stuff to your drawing. Below is a very quick addition just so you can see. What i did was at each elevation i create 3 or 4 more lines to create a closed sketch. I used PEDIT>Multiple, selected my lines(each elevation at a time so you will need to repeat this many times) and used the Join command. You could also use the REGION command which will be a lot faster in this case and still give you valid sections for a loft.

 

You can see in my drawing that none of the boxes line up. I suggest all your boxes end at the same XY coordinates only that they be on the Same Z level as your contour in each case. This will give you a solid "section" of the land.

 

If you need information about the material you are going to remove i suggest you setup some lines laying out your XY area and a line at your Z depth and perform SLICE 5 different times, each time selecting a plane and one of your lines as a slice reference. Keep Both sides each time. You should end up with a solid section(your removal area) and your land which now will be sliced into several pieces. Move the solid section of land and then use the UNION command to re join the rest of your "map".

 

I wont be online for the rest of the day today but hopefully this made some sense, i tried to write it down quickly.

topohelp2.jpg

Share this post


Link to post
Share on other sites
zabilya
Perhaps this thread would be of some utility.

http://www.cadtutor.net/forum/showthread.php?t=8618

 

I traced the contour lines just like you told me

Interesting tip at the link above,do you think it will work out with my stuff, i'm gonna give it a shot

Its getting a bit complicated for a beginner in 3d to understand the tips. i'm gonna try to do something ,i wll get back to you.

Share this post


Link to post
Share on other sites
zabilya
Well from the contour lines you posted i think it would work because its a very small elevation change. The issue you will run into is while you do have elevation lines, the approximation of the land isnt perfect. For instance if one of your lines was at 99' and the land dropped suddenly but but not an entire foot until the next contour line, you are not going to know this and it wont be well represented in the model.

 

 

 

as i've mentioned i've calculated the actual elevation in between contour lines where my grid lines intersect. (dark red color) contour elev.green. This is done for calculation of cut and fill.

than depending on each square elevation, you divide square by areas,calculate area,calculate average of the earth for that area to be cut /fill and that total cut and fill for that square

peace:)

Share this post


Link to post
Share on other sites
rustysilo

This really would be much easier and probably quicker using a civil product.

Share this post


Link to post
Share on other sites
pdxdan11

By civil product do you mean Pro/E or Solidworks? I have been predominately an AutoCad user for years. People have told me not to use AutoCad 3d for model building however I have 3 models which I have spent quite a bit of time on already and I just want to finish them up and render them. At that point I will be willing to learn other programs. For someone like myself who wants to build and render 3d architectural (buildings) what programs do you recommend I start in? Alos what are the best programs to import my 3d AutoCad models into to render them? Thank you.:)

Share this post


Link to post
Share on other sites
zabilya
Perhaps this thread would be of some utility.

http://www.cadtutor.net/forum/showthread.php?t=8618

 

here i'm trying to follow the smart guy's tip

i used a div command i have the top border line divided in 40 segments

but for some reason the marks are to small tried to zoom in but didnt get the same shape and size the guy did

also dont know how to insert marks at the bottom border corner just like he showed

contourtip.dwg

Share this post


Link to post
Share on other sites
shift1313
as i've mentioned i've calculated the actual elevation in between contour lines where my grid lines intersect. (dark red color) contour elev.green. This is done for calculation of cut and fill.

than depending on each square elevation, you divide square by areas,calculate area,calculate average of the earth for that area to be cut /fill and that total cut and fill for that square

peace:)

 

 

 

I understand you have the elevation between the contour lines but what the loft looks like between those contour lines can take on many different shapes. There are options for ruled/smooth fit, you can tell it what angle to enter/exit the lines etc. While this method might give you a good visual representation I dont know how accurate it actually is compared to the real thing.

 

PDX, if you go to the Autodesk website they make a product called civil3d. i think this is what he was talking about. Pro/E and solidworks arent designed for this either. They are mechanical programs designed for assemblies, motion, stress analsysis, flow etc.

 

http://usa.autodesk.com/adsk/servlet/index?siteID=123112&id=3566722

Share this post


Link to post
Share on other sites
zabilya

Can somebody answer on #29 post

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...