Yup... that's pretty much it. A matter of determining the moments and resistance, and deflections. Loads are small, assuming it's steel, shear will not likely be an issue. I'd connect the stringers to the beam fairly rigidly to minimise any torsion in the beam. Check the loads on your columns and you have to use the floor as a diaphragm for lateral loading... I'd consider about 10% of the floor loading and you need some cross-bracing or rigid frames to take the lateral out... done like a turkey.
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So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates
-Dik