Hazard maps and curves

[E.Veliu]

Dear Zoi,

Could you please cite here the source that SB utilizes to compute the uniform hazard spectra? That is, what is the hazard model, the date on the model was released, etc?

I see that after PGA ratios are computed DB provides a corresponding return period, thus I would like to know what is the functional form that SB adopts for the hazard curve in order to interpolate between the anchored values that are provided by the maps. That is, in case the authority provides PGA at some return periods, say 30, 50, 72, 100, 140, 200, 975 e 2475 years, what about the values in between?

Thank you in advance,
Enes

[seismosoft]

SeismoBuild provides the uniform hazard spectrum, as described by the standards that are supported by the program. The description of the spectrum accepts the PGA as an input for each hazard level, which is the responsibility of the user to provide it.
When one PGA is provided, the factors between the PGAs for different return periods are calculated according to EN 1998-1:2004, section 2.1, in page 30.
Seismosoft Support

[E.Veliu]

Thank you for the detailed reply. However, I would like to know what is the value of the exponent "k" that you have adopted for the calculation of the annual rate of exceedance, is it 3?

[seismosoft]

Yes, k=3.
Seismosoft Support