Use of UBC spectra 1

[Solangel]

I'm a young Civil Engineer from a Central America country, design codes used in my country refer dynamic seismic analisis to the same parameters of UBC code, we don´t have a lot of seismic history, however I want to know if is right to use the Ca and Cv seismic coefficients (needed to calculate the values for the UBC ’97 spectra), with the values specified in our design code for my country, knowing that the default values listed are for American seismic zones, for instance Seismic Zone 3, Soil Type “Se” (Soft Soil Profile). However I would like to know if the type of soil is enough to use the UBC spectra.
I'll be thankful for any answer.
Solangel
"God bless you"

 

[Qshake]

The spectra is a wonderful design tool as it is applicable to many situations. This was the intent when it was developed. However, you've hit on the one site specific concern with that equation. As a practicing earthquake/structural engineer who has done much seismic analysis/design I can say that when appropriate we use that same formula for the US. The soil strata couldn't be more varying not only from coast to coast but even in the local area of application wide variation is not uncommon. So feel confident with its use, just make sure that you fall within the categories specified or have an experienced geotech advise on the situation.