Equivalent Deflection Lab Test

Just shooting from the hip...

Your test setup is an upside down, simply supported beam. Since deflection is measured at the load location, I'd ignore any beam beyond the load location. You should be able to back out an equivalent EI (using deflection = P*L/48EI) for the concrete based on your measured deflection, the applied load (and doubling it for the deflection calc b/c the rxn at the middle should be double the load cylinders), and L is the distance between your point loads.

Using your computed EI's for your different load levels, you could then re-run the continuous beam analysis and see how actual EI values change the deflections you had calculated previously.

If I misunderstood what you're going for, I apologize in advance.

Please note that is a "v" (as in Violin) not a "y".

Agree with above. You can't directly compare deflections. The boundary conditions are different. If the beam cross sections are the same then you can back out an EI and use that in beam theory to calculate deflection in the actual case. If the cross sections are different, then you have a more complicated analysis task ahead.