A combination of construction stages may be necessary if, for example, you want to model simultaneous or overlapping construction processes where partial models need to be taken into account and a linear superimposition of the results would not be correct.
In the Load Cases and Combinations dialog box, you can consider such situations in accordance with standards using load factors and generate design situations that cover all constellations for the design.
Combination Wizard
Combinations can be generated automatically; to do this, you need to activate the combination wizard. You can make the corresponding program settings in the Base Data of the model and in the “Load Cases and Combinations” dialog box → “Base” tab.
For more information on using the Combination Wizard, see the Combination Wizard chapter of the RFEM manual.
Editing Settings
You can access the “Edit Combination Wizard” dialog box via the Navigator – Data → “Load Cases and Combinations” → “Combination Wizards” or the menu bar → “Load Cases and Combinations” → “Combination Wizards”.
If you activate the “Consider initial state” option, the “Initial state” tab becomes available. There you can select a load case whose deformations are to display the initial state for the combinations created.
You can also use the ‘“Generate identical combinations without initial state”’ option to generate load combinations with and without considering the construction stages. If this check box is activated, twice the number of load combinations will be generated.
Checking Combinations
Combinations of actions are automatically generated for each construction stage; load combinations for the respective design situation are then generated from the combinations of actions. In the “Load Cases and Combinations” dialog box, you can check all automatically generated combinations in the corresponding tabs.
Combining Manually
To combine loads manually – either as an alternative or in addition to the combination wizard – create a new element in the “Load Combinations” tab. To do this, click the
button at the end of the list. In the “Special options” section, you can make the appropriate settings:
Considering Initial State from
In the list, you can select the underlying stress and strain state. For a classic situation, this is the previous construction stage. If there is no selection option, first define the construction stage to be taken into account.
Considering Construction Stage
Use the list to specify which structural construction stage is to be considered. If necessary, you need to create any auxiliary combinations manually.
Combining Results
To combine results, create a new element in the list in the “Load Cases and Combinations” dialog box → “Result Combinations” tab; then assign the relevant construction stages.
