SSR Analysis Results Overview
If you have computed a Shear Strength Reduction (SSR) analysis, the following results will automatically be displayed when you initially view the model in Interpret:
- the Critical Strength Reduction Factor (SRF) results will be displayed
- the default contour data will be Maximum Shear Strain contours
Results of SSR analysis (Maximum Shear Strain contours)
Stage Tabs for SSR Analysis Results
After an SSR analysis, you will notice that the Stage Tabs will display "SRF: ## (r)". This has the following significance:
- Each Stage Tab which displays "SRF: ## (r)" indicates the results for one iteration of the SSR analysis.
- The iteration corresponds to the value of SRF indicated in the Stage Tab (e.g. "SRF: 1.5" indicates that if you select that Stage Tab, you will see the results for a Strength Reduction Factor = 1.5)
- By default the Stage Tab for the Critical Strength Reduction Factor will initially be selected.
- You can select any other Stage Tab to view results for different SRF values.
- The letter "r" beside the SRF value in the Stage Tab indicates that you are viewing RELATIVE results (r = relative). See below for more information.
Relative Results
The significance of relative results (also referred to as differential results) is discussed in the Differential Data topic. It simply means that you are viewing results relative to a particular stage (the "Reference Stage") of the model, rather than the initial stage of the model.
- In the case of SSR analysis, by default the initial reference stage is the FIRST iteration of the SSR analysis. In most cases this is SRF: 1 (although this depends on the value of the initial SRF, which can be user-defined in the Project Settings dialog, it will not necessarily be equal to 1).
- By default the Reference Stage will only apply to Displacement results. This means that when you view Displacement contours, the results you see will be relative to the Reference Stage (i.e., the first iteration of the SSR analysis).
- The display of relative displacements is useful because it allows you to see only the displacements which have occurred relative to the first iteration of the SSR analysis. Displacements which have occurred in stages prior to the SSR analysis are therefore not included.
- The reference stage can be changed at any time in the Stage Settings dialog. You may also choose to apply the Reference Stage to all contour data, and not just Displacement data. See the Stage Settings topic for more information.
- If you set the reference stage = 0 (i.e. "Not Used") in the Stage Settings dialog, then you will see the results for all stages of the model, including the stages prior to the initial SRF iteration. There will always be at least one analysis stage prior to the SSR analysis.
- Stages prior to the SSR analysis will just indicate the stage number (or name), and will not display SRF: ##.
- The SSR analysis results always appear after the regular staged results, in the Stage Tab ordering.
SSR Results for Multi-Stage Models
Remember that if your original model is a multi-stage model, the SSR analysis is only carried out for the LAST STAGE of the model. SSR analysis is NOT carried out for each stage of a multi-stage model, only on the model as it exists in the LAST STAGE.