Diaphragm Calculations
Diaphragm Calculations can be performed in FEM-Design but you can also run calculations without diaphragms (if the diaphragms have not been defined in the model). Through the different types of calculations the results will be analogous with the adjusted option.


The usage of the diaphragm tool is optimal by storeys for high-rise buildings, but the diaphragm modelling tool is also useful for other engineering problems. The diaphragms could be several regions, but they must be horizontal. The shapes of the diaphragms can be arbitrary and they can be separated also on the specific storey levels. There can be more diaphragm regions on the same horizontal level, yet they will work independently from each other.
Two Diaphragm Calculation Options
There are two different options for the diaphragm calculations: Rigid Membrane and Fully Rigid. The difference between them is demonstrated by the following pictures.

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Calculations performed according to:
Eurocode
Belgian Annex
British Annex
Danish Annex
Dutch Annex
Estonian Annex
Finnish Annex
German Annex
Hungarian Annex
Latvian Annex
Norwegian Annex
Polish Annex
Romanian Annex
Spanish Annex
Swedish Annex
FEM-Design Wiki
You can see a scientific explanation of Diaphragm Calculations in FEM-Design if you download the theory book: FEM-Design v17 Diaphragm and Plastic Theory
You can also find more details about Diaphragm Calculations on the FEM-Design Wiki if you click here.
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