Surveyors measure stockpile volumes on construction and mining sites as well as quarries, aggregates storage sites, or landfill areas. Drone surveying is a game changer in those situations. It is now quicker, safer, and easier to collect data over large stockpiles. However, it can still be tricky to use drone data to generate stockpile calculation reports if you don't know the proper way to calculate them.
The Virtual Surveyor app includes tools that help simplify stockpile calculations and measure them as accurately as possible. You can also generate a user-friendly PDF report or export the results as a .CSV or GIS file. This article provides an overview of all the stockpiles you can create using Virtual Surveyor, and how to apply them.
Overview
- Clean the Stockpile Terrain
- Stockpile Baseline Boundary
- Reference Surface Type
- Material Types for Stockpiles
- Stockpile Calculation
- Results Visualization Options
- Export the Results
- Tips and Tricks
Clean the Stockpile Terrain
It is important to remove objects that hang over the pile before launching a stockpile calculation; you don't want to include them in the material volume calculation. Conveyors and machines—like wheel loaders—are often over stockpiles. In general, the first step is to remove those objects by using Replace Terrain tool.
You can have a look at our Remove a Conveyor article that describes how to remove a conveyor in more complex environments.
Stockpile Baseline Boundary
You need a boundary that surrounds the stockpile. Use the Boundary tool to draw around the stockpile. There are drawing modes that can help speed up the process (as shown in the illustration below).
Reference Surface Type
Select the appropriate reference type depending on the use case. Here are the available reference types:
- 3D Surface
- Flat
- Flat Minimum
- Terrain State
You can choose the reference type in the Volumes group of the TOOLS for Boundary tab.
Freestanding Stockpile
Select 3D Surface, the base surface is triangulated on the vertices of the stockpile boundary; their Z values are very important. It is essential to accurately draw the boundary line around the bottom of the stockpile.
Profile view of a freestanding stockpile: You calculate a freestanding stockpile on a slope the same as you would at ground level.
Stockpile areas are often organized with walled spaces. In some cases, it is not possible to draw a boundary at the bottom of the stockpile. Use a boundary that follows the inside of the walls to create the baseline.
Open wall stockpiles: For an Open wall stockpile, you won't need to manually adjust any of the vertex's elevations, but you should ensure that at least one vertex is placed on the ground in front of the stockpile. Then select the Flat Minimum method to generate a reference surface under the stockpile at that ground level.
Enclosed wall stockpiles: For enclosed wall stockpiles, you'll need to define the flat floor level by setting a specific reference level under the stockpile. To do this, select the Flat method and set the elevation value in the Elevation box.
Cross Sections on Stockpiles: Create cross sections on stockpiles and densify them to analyze elevation changes.
Breakline Under a Stockpile
When there are changes in elevation or multiple tiers of elevation changes at the ground level under the stockpile, you will need to properly model the ground under the stockpile to give it a better estimated calculation. You can do this by drawing a breakline under the stockpile and triangulating a surface under the stockpile. Then select the surface and create the stockpile. Read more about how to do this in our Calculate a Stockpile Over a Bank article.
Profile view of stockpiles over a bank, gradient, and trench: Any type of stockpile that is over a bank, gradient, or trench requires a manually created surface under the stockpile by drawing a boundary around the stockpile then defining the baseline with breaklines drawn at the changes in the slope under the stockpile.
Stockpile Over Time
Compare stockpile surveys over time and create an "Empty Site" of stockpiles to compare different stockpile levels with multiple drone data sets. You can click on the Terrain State drop down menu and choose the reference Terrain State to view the stockpile you are wanting to see at a specific time the drone data was created. This feature is only available when the project contains multiple Terrain States (Peak user only).
Material Types for Stockpiles
Select the material for the stockpile type from the Material dropdown menu. You can create and manage materials using the Material Editor.
Notes! You can change the material after you create the stockpile at any time via the TOOLS for Stockpile tab.
Stockpile Calculation
Launch the stockpile calculation by clicking on the Stockpile button in the Volumes group of the TOOLS tab.
Results Visualization Options
Stockpile inventory results are available in the Selection box in the lower left corner.
Tick the Volume checkbox in the annotation settings found in the TOOLS tab when a stockpile is selected to display the net volume value in the Viewport over the stockpile.
Export the Results
There are multiple options to export the stockpile calculation results and information from the Export tab, as well as options to create a template of your stockpile layers and materials.
You can create a Stockpile PDF report by clicking on the PDF Export button.
You can also export stockpile values as a spreadsheet (.csv) or GIS file (.shp). Set the appropriate export format in the box and click Export Stockpiles.
Tips and Tricks
- You can launch multiple stockpile calculations in one click by selecting multiple boundaries before clicking on the Stockpile button.
- If the stockpiles overlap, use Interpolate Z feature to draw the boundary.
- It is possible to import a DXF file to define stockpile boundaries. For example, if you have to regularly monitor stockpiles that keep the same bases, you can import a DXF bases file.
- Use the top-down 2D mode to get a better volume annotations visualization within the Viewport.