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Irena Kirova, M.Sc.
2025-02-26

Considering Nonlinearities in Response Spectrum Analysis in RFEM 6

Is it always necessary to consider tension member nonlinearities in response spectrum analysis?

Answer:

The need to account for tension member nonlinearities depends on the analysis objective. If the primary aim is to determine base shear forces for comparison with other horizontal actions, neglecting the nonlinearities of tension members is typically acceptable and can be considered a conservative approach. However, for precise design of the tension members themselves, it is essential to consider their nonlinear behavior. Methods such as deactivation should be employed to accurately capture these effects and ensure the integrity and safety of the design.

The image compares seismic forces by neglecting and including nonlinear tension member behavior in response spectrum analysis.
Seismic Force Comparison | Tension Member Nonlinearities
Author

Ms. Kirova is responsible for creating technical articles and provides technical support to Dlubal customers.

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Frequently Asked Questions (FAQ)

Where can I find the update reports for RFEM 5, RSTAB 8, SHAPE-THIN, SHAPE-MASSIVE, RX-TIMBER, CRANEWAY, PLATE-BUCKLING, COMPOSITE-BEAM?

For my NVIDIA graphics card, I need to select between a driver from the "Production Branch" and a "New Feature Branch." Which driver is best suited for RFEM/RSTAB?
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