Settlement of supports on 2 span beam Formulas

Figure out what an equivalent concentrated point load at that location that would induce that deflection would be equal to, then use that to determine your maximum stress the usual way.

I'd use the slope-deflection method since you can easily account for the initial deflection at the support.

Hi chorner26,
I would start from the differential equation for a bending beam. Allows all parameters to be adjusted to your liking.
Keep in mind that a small difference in support relative elevation has a substantial impact.
I only have experience with the Eurocode, but your code will also give limitations and prescribe an approach for multi point supported beams, as the max stress is very sensitive to relative elevation and stiffness of support points.
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