GeoHECRAS can perform an analysis on multiple scenarios at the same time. This is useful, for example, when a comparison of an existing bridge and a proposed replacement bridge are to be analyzed. A scenario would consist of selecting the flow data and one of the geometry data. Computations on the multiple plans can then be performed sequentially (one immediately after the other) using the Analysis | Compute Steady | Multiple Scenarios ribbon menu command. (A similar command exists for unsteady flow scenarios.)
Selecting the Multiple Scenarios ribbon menu command causes the Multiple Scenarios dialog box to be displayed.
This dialog box allows the user to select which scenarios to be computed, the flow regime to be used in the computation, and which scenario result file should be loaded by default when displaying the output results. Clicking the [Compute] button will cause HEC‑RAS to perform the multiple scenario analysis.
Displaying Multiple Scenario Results
After the computations have been performed, the software can display the results from multiple scenarios overlaid on each other for the following output results:
- Cross Section Plot
- Profile Plot
- General Profile Plot
- Rating Curve
- Stage & Flow Hydrographs
- Summary Output
To view the output results, select the Results ribbon menu and choose the output menu command. For example, select Results | Profile Plot ribbon menu command.
The Profile Plot window will be displayed. From the Profile Plot window, select Options | Plans from the menu. The Plan Selection dialog box will be displayed and the user can then select the scenarios (or plans) to display.