Field Stress Statistics

If you are using the Probabilistic Analysis option, you can define field stress statistics (random variables) with the Field Stress option in the Statistics menu.

Field Stress

Before you can define field stress statistics, you must first choose the Field Stress Type (i.e. constant or gravity) in the Field Stress dialog.

This will ensure that the appropriate random variables are available in the Field Stress Statistics dialog, as described below.

Field Stress Statistics

To define field stress statistics:

1. Select Field Stress from the Statistics menu.
2. Select the Add button for each random variable you would like to define. Each time you select the Add button, a new random variable will be added to the list of random variables. NOTE:
3. • If you repeatedly select the Add button, you will see ALL possible random variables that can be defined for the field stress type. You can then use the Delete button to remove variables from the list if necessary.
   • Alternatively, you can select the Add button once for each required variable. Then click on the Property name and you will see a drop-list of all possible random variables, from which you can choose a desired variable.
4. For each random variable, enter the required input parameters.
5. • If you are using the Monte Carlo or Latin Hypercube sampling methods, then you can choose a statistical distribution for the variable, and enter the Mean, Standard Deviation (if applicable) and Relative Min and Max values.
   • If you are using the Point Estimate Method, then only the Mean and Standard Deviation is required for each random variable.

NOTE:

• If the desired random variables appear to be missing from the list of available variables, then make sure that you have chosen the correct field stress type (constant or gravity) in the Field Stress dialog.
• Not all field stress parameters can be defined as random variables. If a variable does NOT appear in the Field Stress Statistics dialog, regardless of the settings in the Field Stress dialog, then this indicates that the variable cannot be defined as random for the probabilistic analysis.