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This object serves multiple purposes, including defining unfactored result cases for AASHTO-based combinations, filtering staged construction results by load type, extracting incremental/cumulative results from staged construction analysis, and combining transient loads such as wind loads, live loads to identify the most critical load effects.

The main purpose of this section is to prepare Staged Construction Analysis results for AASHTO-based combinations. Most of the auto-generated transient loads, such as wind load on the structure, wind load on live load, and live load definitions, automatically generate their result extraction cases and can be directly used in limit states. However, for other loads, such as construction loads or temperature loads, the user must define a case here.

The Result Extraction Cases generated through this process will be utilized in the "Limit States" section.

When selecting result cases from a Staged Construction Analysis, there are several options available to extract results :

1.Result Extraction Method from Stages[Cumulative/Incremental]: Users can choose either 'Cumulative' or 'Incremental'. When the 'Cumulative' option is chosen, the 'Filter by Load Type' column will be activated, allowing cumulative results to be filtered based on load types. This will include all prior stages as well as the results of the selected stage.

For example, if you are analyzing a structure that has been loaded in multiple stages—say, first with dead loads and then with wearing surface loads—choosing 'Cumulative' will give you the total effect of all these loads combined up to the current stage. In contrast, selecting 'Incremental' would show only the effect of the wearing surface load applied in the current stage, without considering the dead loads applied in previous stages.

So, for example, with this logic, the below selection will lead to unexpected results since the DW stage includes all force effects, including dead and imposed loads, as they are not filtered by load type

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However, when you select the incremental effect from that stage directly as seen below, if the wearing surface is a load applied in only one stage, it will be the correct selection.

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Please check the table below to understand the difference between incremental and cumulative result extraction with numbers.

2.Filter By Load Type[None/Dead Load/Imposed Dead ….]: Since different load types may exist in a particular stage, narrowing down the results by load type may be necessary. If the "Filter By Load Type" option is set to "None," the component will extract the incremental or cumulative results from the selected stage without filtering them by load types. However, if it is set to "Dead Load," the component will extract only the incremental or cumulative dead load results and exclude other load types, such as imposed dead or wearing surface loads, from the selected stage. This option filters the results by load type, making it crucial to correctly assign load types to the stages for accurate result extraction.

For example, consider a structure that has been loaded in four stages. In the first stage, a dead load is applied; in the second stage, an additional dead load is applied; in the third stage, an imposed dead load is added; and in the fourth stage, a wearing surface load is applied.

If you set the 'Filter By Load Type' option to 'None' and choose 'Cumulative,' and then select the fourth stage, the results will show the combined effect of all the loads (dead loads from stages one and two, imposed dead load from stage three, and wearing surface load from stage four) up to and including the fourth stage.

Now, if you select the fourth stage and filter by 'Dead Load,' the results will display the cumulative effect of the dead loads applied across the first and second stages while excluding the imposed dead load and wearing surface load. This means that although the imposed dead load and wearing surface load are present in the third and fourth stages, they won’t be reflected in the filtered results. Instead, you will see only the cumulative impact of the dead loads from the first and second stages up to the final stage.

This filtering process allows you to specifically get the cumulative effect of the dead loads over multiple stages, even when other load types are applied in subsequent stages.