calculate if glulam beam to I-beam

Fredrik Olofsson · 28 Sep 2011 at 7:31 PM

Hello

Does anyone know how to calculate if a glulam beam that is 4980*90*450mm can be converted to an equivalent dimension in an I-beam??? I have searched online and tried to find a program similar to Moelven's stock beam program but for steel beams and haven't found anything suitable.

Best regards
Fredrik

Locke · 29 Sep 2011 at 1:36 AM

Yes, it's really just a matter of looking at the tables, but it would have been easier if you had provided a bit more data on the beam.

The support length may vary slightly, but it shouldn't be an issue if you transition from trä to steel.

Fredrik Olofsson · 29 Sep 2011 at 8:41 AM

What more do you want to know? It is to be installed in an opening in a load-bearing wall. It will be replaced with a corresponding I-beam. I have calculated using Moelven's beam program that I previously mentioned a glulam beam but I think it builds too low. And preferably, the I-beam should not be wider than 90mm.

hempularen · 29 Sep 2011 at 9:43 AM

Now I know that I'm a bit boring. But contact a structural engineer. There may be parameters in your load case that you are not considering. That is, whether you are going to do this with a wooden beam or steel, you need a professional calculation.

Moreover, such a renovation (change of load-bearing parts) requires that you file a building notification, and then you will need to present construction calculations, both for the beam itself and for the support points, and how much load they transfer down to the foundation, which may need reinforcement.

Calculation programs from Moelven, etc., are good for assessing the reasonableness yourself (it is a shame to pay a structural engineer to find out that the beam will take up half the ceiling height). But for the precise dimensioning, you need a professional.

Fredrik Olofsson · 29 Sep 2011 at 9:56 AM

There is a glulam beam there today that is slightly too weak (360mm has a bit too much deflection) and according to Moelven, a 450mm is required according to today's new standards. Earlier this year when I checked, a 405mm was sufficient. Someone here must be able to translate the dimension I am asking for into the equivalent I-beam. Building notification and all the bureaucracy required to change something in houses today, but... I wish for a guideline on the equivalent I-beam.

prototypen · 29 Sep 2011 at 9:24 PM

A narrow beam can be dangerous if it is long. It can twist and rest on the platform in the middle.
Consult with a structural engineer who has calculation software.

Protte

Fredrik Olofsson · 30 Sep 2011 at 10:33 AM

Anyone know?

Locke · 30 Sep 2011 at 3:24 PM

Fredrik Olofsson said:
What else do you want to know? It needs to be mounted in an opening in a load-bearing wall.
It will be replaced with a corresponding I-beam. I have calculated using Moelven's beam program that I should use the previously mentioned glulam beam, but I think it extends too far down. And preferably, the I-beam should not be wider than 90mm.

See if you can find the values Iz, Wz, Zv in the beam's technical description.

Granngubben · 1 Oct 2011 at 2:51 PM

The strongest I-beam with a maximum width of 90 is IPE160, (IPE180 is 91 mm wide).

A stronger and stiffer steel beam is VKR160x90x8, (the strongest I found in the tables, with a maximum width of 90). VKR beams are also insensitive to lateral-torsional buckling, which can be an issue for I-beams. Choose VKR!

If a lighter beam is sufficient, there are many, many others to choose from, such as VKR160x90x5, VKR140x80x4, but proper sizing is required to select the right beam.

If you have loads and geometry, perhaps someone can calculate it for you.

prototypen · 1 Oct 2011 at 5:20 PM

Why exactly 90 mm width, an HEA beam is lower but wider.

Protte

Granngubben · 1 Oct 2011 at 5:43 PM

Maximum width 90 mm is TS's request in post #3.

prototypen · 1 Oct 2011 at 5:56 PM

Yes, I know, but is it just that the old wooden beam is 90 or can you cut up the inner ceiling or whatever it is to fit a wider one?

I installed an HEA in the ceiling of the carpentry and cut away 2 cm of the plaster since the old wooden support beam was narrower.

Protte

Fredrik Olofsson · 2 Oct 2011 at 8:47 PM

The line load on the load-bearing wall is 16kN per meter, and in the middle of the opening, the beam should handle 41kN.

Locke · 3 Oct 2011 at 2:27 AM

Do you mean that there is a point load of 41 kN in the middle of the opening?

Fredrik Olofsson · 3 Oct 2011 at 8:40 AM

Yes, it does. Because it is a module joint there that is normally supported by a pillar.