Pick GM Surfaces

If the Probabilistic Analysis Type = Overall Slope, then the analysis can locate many different Global Minimum slip surfaces. The display of these slip surfaces can be toggled on or off, using the Show GM Surfaces option.

The Pick GM Surfaces option allows you to view the Probabilistic Analysis results associated with any individual surface or any combination of surfaces displayed by the Show GM Surfaces option. This is done as follows:

  1. Select the Pick GM Surfaces option from the toolbar or the Statistics menu. (The Show GM Surfaces option will automatically be toggled ON, if it was not already).

  2. Use the mouse to select the desired GM surfaces. TIP – you may need to zoom in first. Surfaces are selected by clicking on them with the left mouse button. When a surface is selected, it will be highlighted by a dashed line.

  3. NOTE: if you accidentally select surfaces that you did not want to select, simply click on the surface(s) again with the left mouse button, and the surface(s) will no longer be selected (highlighted).

  4. When the desired surfaces are selected, RIGHT CLICK the mouse. You will see a popup menu, with two plotting options available – Histogram Plot or Scatter Plot.

  5. Select the desired plotting option, and you will see the Histogram Plot dialog or the Scatter Plot dialog.

  6. In the dialog, select the data that you would like to plot.

  7. Now (this is the important part !!!) – in the dialog, select the Highlight Data checkbox. Click on the drop-down list of data to highlight. At the BOTTOM of this list, you will see an option called Selected Surfaces. Select this option.

  8. Now select the Plot button in the dialog, and the desired plot will be generated. The highlighted data on the plot, will be the data corresponding to the GM surfaces that you have selected.

  9. If desired, you can right-click on the plot and select the Highlighted Data Only option, to view ONLY the data for the selected surfaces. All other plotting options can also be used (for example, export the data to Excel, or the clipboard, for further processing in other applications).

The Pick GM Surfaces option is useful for determining which subsets of probabilistic input data, or safety factor, correspond to any individual surface, or any group of surfaces, displayed by the Show GM Surfaces option.

NOTE: the surfaces are only selected temporarily. If you wish to view data for other GM surfaces, or if you wish to generate a new plot, you will have to repeat the above steps.