Volume Questions
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Volume Questions
I knew a little bit of contours and surfaces now. I have a new question about how to calculate the volume between original and proposed surface and need your help. The proposed surface has some elevations on corners of a limit area. There is two design grades running northsouth and eastwest from the ridge of site(the middle line of the limit), looking like cross section. Could you give me some lightening?

 Posts: 425
 Joined: Mon Feb 14, 2005 1:10 pm
 Location: Tasmania
volumes
I assume you have the existing surface and a design surface already created. If you have a design surface then you need a boundary around the perimeter of the design, in your case the corner limits.
you can get teh volumes either of 2 ways. In the modelling toolbar there's a command 'DSOP' which is the 'surface operations' icon. The right side of the dialog box has the Surface Operations where you chose the 2 surfaces and the operator '' (minus) and then 'Run Operation.
This gives the results in the '.' surface at the top of the list. You can keep this if desired, just highlight and run the Copy command.
The other way is to use the 'AVOL' command or Area Volume  the yellow pie segment icon in Modelling toolbar.
Same as previous but you chose the surfaces then you pick the boundary on screen. The result is shown in the command line.
from the help file  Reports the positive volume and the negative volume and the net volume for each area polygon. If the thickness was calculated as (Proposed  Existing), positive volumes represent fills and negative numbers represent cuts.
The results should be the same. trust this helps
regards Richard
you can get teh volumes either of 2 ways. In the modelling toolbar there's a command 'DSOP' which is the 'surface operations' icon. The right side of the dialog box has the Surface Operations where you chose the 2 surfaces and the operator '' (minus) and then 'Run Operation.
This gives the results in the '.' surface at the top of the list. You can keep this if desired, just highlight and run the Copy command.
The other way is to use the 'AVOL' command or Area Volume  the yellow pie segment icon in Modelling toolbar.
Same as previous but you chose the surfaces then you pick the boundary on screen. The result is shown in the command line.
from the help file  Reports the positive volume and the negative volume and the net volume for each area polygon. If the thickness was calculated as (Proposed  Existing), positive volumes represent fills and negative numbers represent cuts.
The results should be the same. trust this helps
regards Richard

 Posts: 425
 Joined: Mon Feb 14, 2005 1:10 pm
 Location: Tasmania
DESIGN SURFACE
Not much detail given but you can make up a surface with points or 3D lines or polylines. Your ridge line can form part of the model and you may need to add lines forming the 'cross sections' in 3D format at the design grade. Your description is a bit vague.
You will need to run a 3D polyline around the perimeter to limit the surface (volume) calculations. This is also part of the design surface.
The other question re Islope. One of the main problems with this routine occurs when the model doesn't go far enough beyond the design limits.
The left side up/ down slope is in effect the batter (as we call it here). This slope or batter intersects the base and the natural ground at prescribed slopes 1:1 etc.
Not sure if this answers your queries.
regards Richard
You will need to run a 3D polyline around the perimeter to limit the surface (volume) calculations. This is also part of the design surface.
The other question re Islope. One of the main problems with this routine occurs when the model doesn't go far enough beyond the design limits.
The left side up/ down slope is in effect the batter (as we call it here). This slope or batter intersects the base and the natural ground at prescribed slopes 1:1 etc.
Not sure if this answers your queries.
regards Richard