The Equate Materials option is accessed through the Material Statistics dialog. It allows you to equate random variables in different materials, so that the sampling will be identical for the specified variables. This is useful when you have different materials which have some common properties (e.g. cohesion and friction angle) and some properties which are different (e.g. anisotropic bedding angle). This allows the common properties to receive identical sampling, while allowing other properties to differ. In general this should provide more realistic analysis results, compared to running the analysis with no correlation of variables.
To Equate Materials:
First define the random variables as described in the Material Statistics topic.
Select the Equate button in the Material Statistics dialog.
In the Equate Materials dialog, select the Add Group button.
In the Select Materials dialog, select the Materials you would like to equate. Select the Next button.
In the Select Properties dialog, select the random variables that you would like to equate for the selected materials. Select the Finish button. Select OK.
When the probabilistic analysis is run, the random variables which have been equated for the selected materials, will have identical sampling applied. This means that for each sampling, the exact same value will be generated for both variables in two different materials, if the two variables have exactly the same distribution parameters.
See Tutorial 27 for a demonstration of the Equate Materials option.
NOTE: when you equate material properties, the random variables which are equated must have exactly the same Distribution type and shape, or else you will see a warning message that the variables cannot be equated.