You should be super lucky if you could find someone here who did the similar simulation!! I would suggest why not, you perform some simulation and then ask for assistance here.
what's your question? This looks straightforward. Analyze the steel structure as a whole ignoring fasteners. Then once you have some forces at the joints model those separate to look for localized stress in the fasteners.
Personally, I would ignore the strength of the concrete and just ensure you add it's weight in the analysis.
If you are using Simulation, you better know it's weaknesses. If you're doing buckling, you will need nonlinear because the linear package only does Euler buckling which can get you into some dangerous situations if you are doing bridges. Also, I would run everything as solids and a very dense element count. The beam and shell analysis is good for nothing.
Also, back everything up with hand calcs...
IF YOU DON'T UNDERSTAND STRESS ANALYSIS, DON'T USE FEA!
what are you looking for ?!?
why do you need FEA?!?!?
Can you say