Measuring the volume of a cut and a fill.
Do you need to measure the volume of a fill or a cut in a quarry? Or you need just to get a digital terrain model (DTM), and the surveyor will not arrive soon enough, but you need the result now.
The application Almagest Volume Measurement allows you to measure the area of sections bounded by a maximum of 100 points connected by straight lines in real time. These points must be measured, taken from memory, or set via the keyboard. The measured area is projected onto an inclined reference plane defined by its points (3D). Volumes are automatically measured by calculating the digital terrain model (DTM) in the local coordinate system, where the first base point is taken as the origin.
It is possible to work in local coordinate system: to do this, you need to load at least one arbitrary point P, Lat, Lon, H into the group of base points (you can do it at least at the equator, then 0,0,0,0) , and then load points in local coordinates in the format P X Y H (you’ll have to separate by spaces 44 456.56 -856.34 111.55).
For obvious reasons, there should be more than three points in the foundation base (and for the "extended base" mode (this means a certain area that has been increased in area), there should be more than three points for the fill/cut group).
There are two surface treatment modes:
- mode (1) - while surveying we remove/load the base points of the material, and then proceed to the set of survey points of the body of the fill. The surface of the fill includes the boundary points of the foundation.
- and there is a special processing mode(2) - when the extended foundation sets us only the plane by which we understand what is the cut and what is the fill. The extended foundation points are not included into the final triangulation (so there can’t be one (two) points in the group). As a result, the surface of the body is projected onto the expanded foundation.
1. Wait for the fixed GPS position when the status icon on the top left is no longer visible.
It is better to start from the middle of the foundation contour, since the application will not allow you to record a point if it is 1 km away from the first point. You need to go around the perimeter of the embankment (points are allowed inside, for a more detailed survey of the foundation, when the embankment is not yet filled out).
Press "v" to save the survey at the end of the survey of the foundation contour or in the process of it.
2. When you click on it, you will be prompted to edit the captured points (pink background of the foundation points), if you do not need to edit, click the "v" button again and proceed to shooting the fill points (blue background when editing). The points of the fill should not go beyond the contour of the foundation! It will remind you once your position goes out of the boundary to ensure your work is limited in a predetermined area. Press "v" to save the shooting at the end of shooting the points of the fill or in the process of shooting. The presented list of points allows you to view all the points, and by clicking the line you can edit the point (you can change the latitude-longitude "LL", as well as the cartesian coordinates "XYZ", but not more than for 1000 m. Editing can be useful, for example, when we know that the foundation points are located at the same level, but GPS accuracy is not exact to solve this result, and manual editing allows you to specify the location of points. (Manually editing points and using polar coordinates also allow you to shoot terrain by squares).
N. B. It is advisable to conduct high-precision GPS surveys connecting to external RTK GPS receivers through Bluetooth.
The latest stage of accuracy enhancement uses the L5 band and is now fully deployed. GPS receivers released in 2019 that use the L5 band can have much higher accuracy, pinpointing to within 30 centimeters or 11.8 inches.
3. In the next window, you can change the project name and add notes. Import/export points (in P, Lat, Lon, H format). Along with exporting to TXT, script * export of *.SCR is available (a set of commands for building a surface from 3DFace to Autocad. You need to drag from Explorer to Autocad desktop and the surface will be built automatically)
- clicking "Results" opens a new window with an already built triangulation that is available for:
- when you click on the edge, it changes colour to red and the button of “swap edge” becomes active. If swap is possible in this triangulation, clicking on this button will allow you to approximate your measurement with the existing terrain (just in case, let me remind you that you need to shoot in the characteristic places of the terrain break (elevation differences, peaks, hollows)
(Planned: In addition, the application allows you to build a horizontal contours lines on the site. Using them, you can find the lowest point, analyze the water drop paths from the site.)
Double tap SHIFTS CENTER OF ZOOM - double tap shifts the center of the zoom.
https://youtu.be/gxceDyb0Bjo - AutoCAD allows you to convert surfaces and objects with thickness to 3D bodies.
https://youtu.be/u-RJFKfTKLA -Earthworks calculator
https://youtu.be/rtU9BtJ9TGo - Import Survey Points
It may be interesting to see my work. review of the apps:
- Auto level surveying calculations + Ñollimation https://play.google.com/store/apps/details?id=com.niveler
- Spreadsheet interpolation https://play.google.com/store/apps/details?id=com.kurantsov.interpolationstationing