I have a spanof 9m that I bridge with a (as yet unspecified) beam. From this beam hangs a load (a pipeline), right in the middle, of 4.295 kN. The beam is simply supported. I want to use an IPE steel beam. How do I go from here to specifiying the exact size? I'd appreciate a specific answer, but more importantly a walkthrough.
I understand I have a bending moment of 5.163 kNm. Now I need to divide this moment by the moment of inertia (that I can find in the right table) and I arrive at a stress. So my question is, which specific of the many moments of inertia my Lölner Stahlbautabellen list is the right one, and what is a decent assumption for max stress, and what margin of safety to apply.
The purpose of this question is a) to arrive at a size that's no too far off, for puprpose of a drawing and maybe cost estimates, and b) to educate myself a bit. Before the structure is built, we will run this by a structural engineer, which brings me to purpose c) not to look ridiculous with a horribly under- or oversized beam.