Analysis scenarios¶
A stability check is rarely a single one: static and seismic conditions, the slope before and after the works, high and low water table. With scenarios all these analyses live in the same project, each in its own tab, with its own data, its own Undo/Redo, its own calculation and its own results. They are then compared in a table, recalculated all at once and collected in a single report.
The scenario bar¶
Above the drawing there is the scenario bar:
- one tab per scenario (at first there is only Scenario 1): a click activates the scenario, a double click renames it, a right click opens the scenario menu;
- + creates a new scenario as a copy of the active one (Duplicate scenario);
- on the right, Scenario comparison opens the comparison table and the Scenarios menu collects all the commands.
The active scenario is the one shown in the drawing and the one all Slope commands act on (data, works, water table, F5 calculation, Recompute, report, exports). When switching tabs, the scenario you leave is kept exactly as it is, Undo history included. Scenarios cannot be switched while a calculation is running.
Creating scenarios¶
From the Scenarios menu (or right click on a tab):
| Command | What it creates |
|---|---|
| Duplicate scenario (also +) | an exact copy of the active scenario, results included |
| Duplicate as static (no earthquake) | a copy with the earthquake disabled |
| Duplicate as seismic | a copy with the earthquake enabled, using the kh and kv coefficients of the General data; if they are zero the program says so and they must be set in the General data of the new scenario |
| Duplicate as pre-construction (works disabled) | a copy with all intervention works (walls, piles, anchors, reinforced earth) disabled |
The new scenario is inserted right after the active one and becomes active; the program asks for its name and suggests one (Static conditions, Seismic conditions, Pre-construction). In the static, seismic and pre-construction variants the copied results are cleared, because they no longer apply to the modified model: the scenario must be recalculated.
The other menu commands: Rename..., Move left, Move right (the tab order is also the order in the report), Delete scenario (not available when there is only one scenario) and Export scenario as .stax..., which saves the active scenario as a project of its own.
Each scenario is a complete model: any data can be changed (geometry, stratigraphy, water table, loads, works, method, grid of centres, partial factors), not only earthquake and works.
Scenario comparison¶
Scenario comparison opens a table with one row per scenario:
| Column | Content |
|---|---|
| Scenario | scenario name |
| Method | calculation method |
| Earthquake | Yes / No |
| kh, kv | seismic coefficients (when the earthquake is active) |
| Water table | Yes / No |
| Active works | number of active intervention works |
| Fs min | minimum factor of safety of the last calculation |
| Required Fs | factor of safety required in the General data of the scenario |
| Result | Verified, Not verified or Not calculated |
Rows are coloured according to the result (green if verified, red if not verified). Below the table the most critical scenario is shown, with its Fs. The buttons:
- Recalculate all runs the calculation of all scenarios, one after the other, and returns to the starting scenario at the end. Stop halts the cycle between one scenario and the next. A scenario with inconsistent data is skipped with the note Inconsistent data; a scenario whose calculation does not finish shows Analysis not completed.
- Go to scenario activates the scenario of the selected row.
- Copy table copies the table to the clipboard, ready to paste into Excel or Word.
Recalculate all is also available directly in the Scenarios menu.
Scenario report¶
With several scenarios, the calculation report command opens the Scenario report window:
- Scenarios to include in the report: all (All button), the active scenario only (Active scenario only) or a selection;
- Include the comparative summary of scenarios: at the start of the report, the summary table with method, earthquake, water table, works, minimum Fs, required Fs and result of each scenario.
The report is a single document: general part and theory once, then the summary, then one chapter per scenario with the data, results and drawing of that scenario; the table of contents is nested by scenario. With a single scenario the report is the usual one.
Scenario DXF¶
With several scenarios, the DXF export opens the Export scenario DXF window:
- One DXF file per scenario: one file per scenario, named with the given base name plus the scenario name;
- A single DXF file with the sections side by side (one layer per scenario): all sections in the same drawing, next to each other, each with its title and its Fs, with layers prefixed by the scenario number and name.
Saving¶
- A project with a single scenario is saved as usual in .stax format.
- A project with several scenarios is saved in .stapx format (a single file containing all the scenarios and their summary). If a project with several scenarios is saved with a .stax name, the program warns and uses the multi-scenario format.
- Opening a .stax file gives a project with one scenario, to which scenarios can be added.
- To hand a single scenario to someone using a previous version: Export scenario as .stax....
Example¶
Retaining wall on a slope in a seismic area:
- Scenario 1, renamed Static: geometry, stratigraphy, water table, wall. F5.
- Duplicate as seismic → Seismic: kh and kv from the General data. F5.
- From the Static scenario, Duplicate as pre-construction → Pre-construction: the wall is disabled. F5.
- Scenario comparison: you see at once which condition governs the design and whether the works bring the slope above the required factor.
- Scenario report with the summary: one document to deliver.
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