VERSION 1.0 SPRING 2018 ADVANCED MINE PLANNING – VOLUMES AND 3D SOLIDS VULCAN – OPEN PIT MODEL PRESENTED BY: DR. ANDREA BRICKEY. SOUTH DAKOTA SCHOOL OF MINES ADVANCED MINE PLANNING – VOLUMES AND 3D SOLIDS In this Lab session, we will learn and/or practice the following: 1. 2. 3. 4. How to link polylines into a 3D solid How to correct issues with polylines How to calculate the volume of a solid How to assign a density factor and calculate mass 1 Open your OPENPIT Vulcan project Steps: 1. Open the appropriate file directory and select Envisage 2. Select the correct .dgd file. 3. Turn on the ORELINES file under the design database folder. Rotate the orelines so that you can see them 3-dimensionally. 2 Go to the pulldown menu Model → Triangle Solid → Create We will use the defaults for now, but under End Plates, check the Construct first end plate and Construct last end plate. Select OK. 3 Remember that the yellow box at the top of the window will tell you what to do next! Now select the first string on the left side of the orebody. Then select the next string. You will now be prompted to assign a color to the solid. You will now see that a surface has been created linking the two polylines together. 4 You can now select the next string and then the next and so on… Oh, No! You just had crossing surfaces. Let’s check to see what is causing this problem. Rotate around where the orelines have indicated a problem. It looks like we have some straight lines sticking out of our polygon. That is causing the surface function to fail. Let’s fix this. 5 To fix this, we can delete these points that are not representing a volume. To do this, we need to use Point Delete. Design → Point Edit → Delete (remember to look at the yellow box for instructions!). Let’s now select the first polygon with the issue. Note that the polygon will change colors and you will now see an + where each point is located. Next, we select the point we want to delete. Now, confirm that you selected the point you want to delete, or you can reject the deletion. 6 Great! We just deleted our first point. But note that you are still active in the Point Delete Model. To exit this, right click with your mouse. Note that our polyline has now returned to the original color and that our ORELINE Design Layer is now red. We can now hit the save icon. We need to repeat this action two more times. To easily access the previous command. Right click in the design window. You will see the following box displaying your most recent commands. Select Design→ Point Edit → Delete You might need to delete more than one point on the next polygon. But make sure you delete all of the points! Since we now know that our polygons might have some issues, let’s do a few more checks before we try to make our solid again. Next select all of your polylines by clicking to one side of the orelines and holding down the left mouse button, drag it to the other side of the orelines. It will make a large box around the orelines. When you let go of the mouse button, the lines should turn a different color. 7 While hovering the cursor over one of the selected polylines, right click your mouse and select Properties in the pop up window. Check the Closure toggle and make sure you have selected Close. Now click OK. This will make sure that all of the polylines are closed, i.e., making a completely connected loop. You will need to save ORELINES after this step. Ok, now we can go back to making our solid. Go to the pulldown menu Model → Triangle Solid → Create Start with one end of the orebody and work your way to the other, connecting all of the orelines. 8 Once you have completed this, right click your mouse twice. Next, you will be prompted to save your triangulation. If you are happy with your triangulation, click Yes. You can change the name of your Triangulation, or you can keep it as orelines. You can also change the color if you want. 9 Now check the box next to “Construct first end plate” and “Construct last end plate” After you have selected all of the lines, Select “Save”! You can change the name of the triangulate or the color. Then select “OK” Vulcan uses an algorithm to create the solids and they are not always perfect. We need to check our surface to make sure it is a true solid. You can do this check by clicking on the solid and then right-clicking. You will be given a menu and you need to select “Check” 10 11 You can save any issues found as a layer. Otherwise they will be generated as an overlay and will not be saved, but will be visible on the screen temporarily. Click next 12 The same is true for this window. Now click “Finish”. After Vulcan runs the test it will provide you with a report. If any of the tests fail it will tell you and indicate where the issues are found. 13 Calculate Volume First way…..click on the solid and right click and select Volume. Before calculating the volume, Vulcan will also check the triangulation. You can also input a density here. Make sure you are using the correct units!!!!! 14 This tells us that the volume of the orebody is 184,703,125 cubic feet! How do I know that it is cubic feet, well that is because we brought in data that was in feet and we told Vulcan that we were working in feet, not meters or yards. I can now convert the volume into cubic yards by dividing by 27! We have 6,840,856 cubic yards! If we had a density of 2.3 g/cm3, how many tons of mineralized material do we have? Answer: 13,271,262 tons. Let’s do this again, but let’s figure out the tonnage by elevation. This is important for mining because we often mine the material by level. For this example we need to have a block model….and lucky for us, we already have one created for us! 15 Please download the bmf file from D2L and copy it to your Vulcan Folder where your dgd file is stored. Block → Advanced Reserves → Advanced Reserves Editor Give your Reserves file a name….I named mine Tonnage and then select the block model that you downloaded from D2L. Next, select the Breakdown Fields under Variables and check the Breakdown by Bench box in the lower right corner and put 50 as your Bench height. 16 Now we need to set our Grade Variables. Here we put in our density value (remember we have a density of 2.3 g/cm3 but we need to convert that into short tons per cubic ft. We want to report out short tons and we are using feet as our unit of data. We need to tell Vulcan this. We also need to select our grade value from the block model and indicate how we calculate the total weight. 17 Now we need to select our solid which we are using to calculate our tonnage. Click on Regions – Triangulations. 18 19 20 21 Check the total tonnage and volumes…..do they check out? You can change the headings to better reflect the data units. The AU grade is t. oz/ton and it is the average grade of all of the material on that bench within the triangulation. This tonnage value is the geologic resource. It is not necessarily minable or economic. Remember that! NEXT STEP Do you remember how to measure distances? 22 You will need these to answer some of the questions in the lab. Take a moment to play around with these functions. Don’t forget to complete your Lab Assignment! The End…..for now. 23