Stiff Soil and 2 to 3 storey bldg resonance

[Quence]

To those designing 2 to 3 storey building with stiff soil profile.. I heard they are in resonance.. do you notice this too and what is your experience on it? Any quick formulas to check the resonance values of the stiff soil and storey height? Geotechnical engineers usually just give you the bearing pressure of the soil and don't usually give you specifics about the resonance of the soil and structure and you need to double check on this before you can scrutinize from the geotechnical at length or in any technical details...

 

[WARose]

If you are using the ELF procedure (for seismic) in the code.....you don't have to worry about that as that is accounted for with the site coefficients in the code. Furthermore, saying a site and a building will be at resonance during a earthquake is impossible for anyone to say (for sure) because there are too many variables involved. (Starting with the forcing frequency of the event.)