Question:
When designing seismic equivalent loads with a Response Spectra Analysis (RSA) in RFEM, how can I apply the modal response parameters I-e/R according to Sect. 12.9.1.2 in the ASCE 7-16 to my results?
Answer:
The modal response parameters can be set in the RF-DYNAM Pro - Equivalent Forces add-on module under the Response Spectra tab. In the Code Parameters table Type of Spectrum Modal Response Parameters, the default is set to "No Modification". This setting can be seen in Figure 1.
Changing this to "Force Related" in the drop-down window will divide the response spectra by I-e/R based on Sect. 12.9.1.2 [1]. Additionally, in the Code Parameters table Coefficients, the Seismic Importance Factor (I-e) and the Response Modification Factor (R) can further be set.