Your StopeExamine License Has Expired:
Description: Requires a new StopeX license.
Solution: Download new license from the link provided by Cavroc
Invalid group specification
Description: For geology, input geometry file/s (.stl) missing.
Solution: Import the missing geology files
No Key is plugged in – Please use the USB key attributed to your StopeExamine license.
Description: Overwriting of “temp.log” file.
Solution: Delete “temp.log” file from the folder where FLAC project is running/locate, then, re-run the simulation.
Overflow error in calculation
Most likely it is a backfill issue.
Solution: Check that all your excavated stopes are getting filled.
Save file created by later version of flac3d.
Description: This error pops up when your FLAC3D software is not updated to the latest version.
Solution: Update FLAC3D by creating an account on Itasca website and following this link: https://www.itascacg.com/software/FLAC3D
step1.stl does not exist
Description: This error is often associated with incorrect naming of the geometries associated with mining steps or if user has forgotten to include the mining step geometries in the working directory.
Solution: User must ensure that all geometries associated with mining excavations are included in the working directory in this format: step#.dxf or step#.stl. For example of total model mining steps are 3, user should include three geometries in the working folder with these names: step1.stl, step2.stl and step3.stl
Model takes a long time to solve the initial step (prior to any mining step) and is not reaching an equilibrium
Description: This is most likely related to the equilibrium of the pre-mining stresses. The gravity, insitu stress, rock mass properties and the boundary conditions should be assigned in such way that they are in an equilibrium state prior to any mining steps. For example if rock properties are extremely weak or stresses are unrealistically high, it can lead to ongoing failure/yield even prior to any mining excavation and model instabilities
Solution: Check the followings:- If topo is included, ensure that the boundaries of the topo geometry extends out enough and is more than the “Model Boundary Offset”. This can be checked by plotting the zones in FLAC3D- If topo is not included, ensure that correct “Ground Surface Elevation” is assigned correctly under “Insitu Stress” section in StopExamine. Note that ground surface elevation should be in RL (relative level) and should not be left as zero.- Ensure that insitu stresses are assigned correctly, in particular ensure that they are orthogonal- Ensure that rock mass properties are assigned correctly.- Plot zone’s state in FLAC3D to check if any part of the model is yielding at initial state.
Model takes a long time to solve after the initial equilibrium step and is not reaching an equilibrium.
Description: This is usually because lots of progressive damage is happening in the model.
Solution: Things to check:- are stopes backfilled in reality and not backfilled in the model?- Too many excavations in each mining steps, make sure two stopes next to each other are not mined in a same mining step- Make sure rock properties are realistic and lithological boundaries are defined correctly - Check the stress state and make sure it is orthogonal
Drive development is backfilled
Description: This is related to how the backfill geometry is defined and also whether Development option is selected.
Solution: One of the following should fix this error:- Make sure development geometry sections that are not to be backfilled are not included in the Backfill geometry.- Always enable the development option and include its geometry separately.
Stresses are negative
Description: FLAC3D uses a mechanical engineering convention and negative compression. Tension is positive.
Solution: This is ok and is just related to FLAC3D stress convention. Always remember that negative stress is compression and tension is positive.
Maximum principal stress not shown correctly
Description: FLAC3D uses a mechanical engineering convention and negative compression. Tension is positive. Therefore maximum principal stress is the greatest negative value which is the smallest absolute value. So, maximum principal stress is actually minor principal stress for mining convention.
Solution: Always remember that maximum principal stress in FLAC3D represent the minor (and visa versa) principal stress in mining.
A JavaScript error occurred in the main process
Description: This error often occurs when updating the StopExamine GUI file (.exe file).
Solution: If this error occurs when using the GUI, delete the stopexamine.js file from this location: C:\Temp
Does not exist
Description: This error often occur when backfill option (or other components like topo, etc.) is selected but no geometry file is uploaded.
Solution: If MAP3D option is not selected and Backfill option is included make sure that a geometry filename is selected. Same applies for other model components like development, topo, historical, etc.
Zero stiffness in grid-point
Description: This error often occur when the topo geometry does not extend enough to cover the boundaries of the model.
Solution: Plot the topo geometry using the Geometry plot item and model geometry using the Zone plot item and make sure topo extends beyond the model boundaries. If not, extend the topo boundaries in a CAD package or reduce the model boundary offset.
Unknown first token at line #! Abort reading the file
Description: This error is often related to situations when import mesh option is selected but incorrect mesh file is selected.
Solution: Make sure, if the Mesh Import option is selected, that appropriate mesh file is uploaded. The FLAC3D mesh (or grid) files often have a .GRD or F3GRD extension.
Integer must be between 0 and 4294967295
Description: This error is commonly associated with having large number of significant digits for the coordinates of the geometries
Solution: If using the original mine grids, the model geometries may need to be translated so that x, y and z coordinates have less than 8 significant digits. If importing models from Rhino, make sure that units are not scaled down to a millimeter unit system and make sure always using the unit systems in meters and not millimeters.
