Seismosoft | Earthquake Engineering Solutions

I am a new user of SeismoMatch, but an experienced user of RSPMatch. Norm Abrahamson notes that RSPMatch requires many spectral ordinates that are equally spaced in log scale (I've used 271 or more for target spectra covering 0 < T < 5s). I've noticed that SeismoMatch doesn't always achieve tight spectral matching and suspect that .02s period step isn't sufficient.

Hi JKHoward,

We are not sure we followed your query.

You seem to be asking/suggesting for the possibility of using period steps different from 0.02s to be introduced in SeismoMatch, right?

However, in reality, such feature is already present (Settings -> Response Spectra), as described in the Help System, not?

Let us know, please.

Seismosoft Support

In SeismoMatch version 22, the software does not correctly calculate the design spectrum according to the ASCE7-16. for example, it calculates the SD1 parameter incorrectly for soil type D with SS=1.979 and S1=0.705. Please check and correct the spectrum formulation of ASCE7-16.

The spectrum is calculated according to section 11.4 but with the adaptations of the spectrum described in section 21.3 (see section 11.4.8). We checked out our code, but it seems that it is correct. Do let us know, if you agree with this implementation.
Thanks
Seismosoft Support