Log File
Each time a RS2 analysis is run, a LOG file is created which summarizes a few key analysis parameters from the finite element analysis (e.g. number of iterations, convergence history etc). In RS2 Interpret, the user can select Log File from the Analysis menu to view a log file for solid, select Log File from the Groundwater menu for fluid, select Log File from the Thermal menu for thermal.
This will display the LOG file in its own view. The LOG file information can then be copied to the clipboard, saved to a file etc, if desired. See the Report Generator topic for more information.
WARNING MESSAGE WHEN LOADING FILE
Maximum number of iterations
A warning message is displayed in the Interpreter when a file is opened, and the number of iterations has reached the maximum number allowable. This occurs when the prescribed tolerance in the iteration process of the plasticity analysis was not achieved, during the RS2 analysis. This means that the program did not find the equilibrium state for the model. The Convergence history for a RS2 analysis is recorded in the LOG file.
NOTE: the Maximum Number of Iterations and the Tolerance required for convergence, are specified in the Project Settings dialog in the RS2 Model program.
If this warning message appears, this can be the result of a number of things, including:
- The model has no equilibrium state. Basically you get collapse and continued deformation. A stable model will generally require some type of support. In some cases, this can be caused by underestimating the strength of the rock mass, or overestimating the initial stresses, either of which can lead to this behavior.
- The number of iterations is too low. The default number of iterations is 500, this can be increased in the Project Settings dialog in the RS2 Model program. In models where a lot of failure and plasticity is occurring, a higher number of iterations might be required. A way to determine if this is the case is to watch the tolerance as the Compute engine is running. If the tolerance is getting smaller as the maximum number of iterations is approached, then you may want to increase the number of iterations. If the tolerance is bouncing all over the place with no obvious reduction, then the most likely reason is that the model does not have an equilibrium state (see #1, above).
Even when the maximum number of iterations has been reached, the results can still be meaningful if you realize that they are not the equilibrium values. They do give you the trend of the stresses, failure and displacements.
No boundary condition for a model
When a model does not have any restrains (except for dynamic models), the results will be undefined. For such cases, a warning message will pop up in the Interpreter when a file is opened. The warning message will also be output in the log file. Users can look for these message in *.log (for solid) or *.low (for fluid) or *.lot (for thermal) files.
Auto Update
Log files are available after compute. Thereafter, if changes are made in the model, and being re-computed, the new results will be automatically updated to the log files. See the RS2 Interpret topic for more detail about auto update.