Calculation of beam

[jorgen_a]

Thank you, both Granngubben and Locke, now I feel a little bit wiser.

 

[Granngubben]

One can also handle some of the moment out at the stockpiles.

Good idea! I ran a small FE-calculation on a frame with HEB120 in both the beam and the column, (moment-resistant corners, translationally locked column feet). At a 2.6 kN/m load on the beam, it deflects down about 7 mm, see attached deformation image. (The calculation model is a half-model due to symmetry, therefore only half of the frame is shown.)

Important conditions are that the corners are moment-resistant (e.g., welded), and that the column foundations can support both vertical and horizontal load.

This feels like the right way to construct with given conditions on beam height and span.

 

[Granngubben]

Important conditions are that the corners are rigid (e.g., welded), and that the column foundations can carry both vertical and horizontal loads.

If the column foundations cannot carry horizontal loads, the column feet will shift 22 mm laterally, and the beam will deflect downward 15 mm, see the attached deformation image.

The beam then bends out as a simply supported beam, and the deflection can be compared to the analytically calculated one:
delta = 5qL4/384EI = 5*2.6*5350**4/384*210000*8.64E6 = 15 mm

Remarks:

• Since I do not know the ceiling height, I have assumed a guessed column length of just over 2 m. The results will of course be different if you have, for example, 1 m or 7 m ceiling height.
• If the conservatory connects to a building and there can be a snow pocket or snow sliding, etc., the loads can be much higher than what I have calculated.
• If it is difficult to arrange the column foundations for horizontal loads, an alternative may be to connect the column feet with a tie rod (e.g., flat bar 50x4 in/on the floor).

Good luck!
Feel free to tell us how it turned out.