Seismosoft | Earthquake Engineering Solutions

Just to be clear and rule out the potential units issue: 1. When you define the time history curve, you specify a factor of 0.01 to get cm to m. 2. When you define the loading, you specify a factor of 1.0, since you converted the units in defining the curve. If these are true, I believe you are corr...

You can place a node in the exact center and connect it to the corners with rigid links. Depending on your intended model, you may have to use rigid links to more than the corners.

If the exact center of mass has, indeed, not been defined, then you likely have eccentric mass distributions at one or more levels, which would indeed produce multi-directional displacements, even if the stiffness is symmetric. Both mass and stiffness must be perfectly symmetric in order to expect n...

This looks as though it could be a units problem. I typically load accelerograms in units of g. I typically use units of inches and seconds. So, when I apply a particular accelerogram as a nodal loading, I have to specify a factor of 386. Just a thought, but double-check the scale factor you applied...

The Help system has a lot of good information on 'Target Displacement'. I typically don't use auto-calculated target displacement, but specify my own. Start with a reasonable guess. If that doesn't push it far enough, increase on the next run. If that pushes too far, you can reduce on the next run. ...

You should be able to manually generate your CMS, save to a text file, and define the target from the file, rather than auto-generating a response spectrum.

Ss and S1 are typically read from maps or obtained from online tools. The best option is the ATC app. USGS also has an app which can be used but the values are geomean while asce used RotD100. You can use ATC app values directly or adjust usgs values. https://hazards.atcouncil.org/ These are for US ...

I would like to add that this is not unusual. One of the developers of spectral matching techniques has stated that they discard approximately 80% of the records they generate through spectral matching. As noted by the Seismosoft team, it is important to have a reasonably close match to shape and am...

Hi Koloubos. I assume you are referring to an 'equivalent sdof' used in direct displacement based design and analysis. I don't think you will find that, as there are multiple means of making that determination in the literature, while SeismoStruct is a full model with no need to reduce to an equival...

Many Japanese records are very large, with 60,000 or more data pairs. One option is to specify a frequency of 2 and double the specified time step to read only every other value instead of every value, essentially cutting the record size in half. I have used this before several times. It will be imp...