Change the Moment of Inertia of a Standard Steel Section

[hugofcruz]

Hello,

I am calculating a continuous composite beam in ARSAP. I've calculated in Excel the moment of inertia of a composite beam, for example:

Beam HEA340

Steel Beam - Inertia = 27690 cm4

Composite beam - Inertia - 80599 cm4

So, the composite beam as a inertia 2.91 higher than the inertia of the steel beam.

I want to define a standard steel section (european section ranges) - HEA340, mantain all the proprieties of that section, so i can use the "STEEL MEMBERS DESIGN MODULE" but i want to change the Inertia (Y-Y direction) to 80599 cm4 instead of 27690 cm4.

I've tried to use the RC Beam, define my HEA340 (i didnt consider the radius) and then changed the material to steel. In this case i can use the "STEEL MEMBERS DESIGN MODULE"  but some of the section parameters are not correct, so the design is incorrect too -  CHECK PDF FILES attached..

Maybe Rafal.Gaweda has an answer for this problem.

Thanks for your help.

Regards,

Hugo Cruz

[Artur.Kosakowski]

You can try this approach:

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[hugofcruz]

Thanks for your help.

I've tried that aproach but it didnt work. Some of the parametrs needed in the Steel modul design are wrong according to that aproach, so the design does not comply with the Standard.

[Artur.Kosakowski]

Perhaps that would be the solution (I'm sorry for late answer but it has been just now I thought about such possibility) :

1. Use the approach from the message 2 for static analysis (or change the value of E of the material assigned to the standard HEA 340 section to match the increase of IY)

2. For the steel design create the group with that element and HEA 340 as the section 'to find' (mind the material for E increase - us the one with the standard value of E)

3. Run the design of this group

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[Anonymous]

Hi, 

I just wanna know if this design approach has worked for anyone 'cause I am now stuck in a similar situation?

Thanks