Effective Stiffness Modifiers

Effective Stiffness Modifiers

In ProtaStructure, effective stiffness modifiers of the slabs could be adjusted for different analysis methods. One of the method is using the “Finite Elements Floor Analysis” option independent from the building under vertical load cases only. This method analyses the floors by isolating them from the building analytical model. All horizontal load cases are ignored. Therefore, only the out-of-plane deformations are calculated. 

The other method is Finite Element Analysis by including slabs in the global building model for all load combinations. This method includes slabs in the building model and executes the analysis for all load combinations. The cracked section option could be considered in load combinations where earthquake, wind, soil pressure, or temperature difference load cases exist.
Stiffness modifiers for cracked sections stated in the Turkish Seismic Code are automatically created and used. For different codes, cracked section stiffness modifiers should be set. For uncracked sections, slab stiffness modifiers should be entered in the relevant field by the user. In this article, model investigated in both analysis methods exported to SAP2000 one by one and analysed again.
We present this design guide to your attention with the hope that it will be useful. You can find the guide as a PDF file in the attachment.​



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