BS5950 steel column calculation anyone?

[skyblob]

Hi.

My Local Authority needs calcs for a steel corner support column I'm proposing in my extension.

It will be approx 2.2M tall, 80x80mm square x 5mm wall. Axial loading (dead load + imposed load from snow) will be maximum of (from a rough calc) 2.4KN. I have no access to BS5950 without buying it, but Corus Steels seem to have all the tables where I can look up Axial load capacity of their tubes, and something called d/t ratio. I don't know where to work out buckling load, and I'm not quite sure what is meant by an axial load "capacity". I'm sure this need not be too complex, and I'm equally sure my column is adequate.
-Any pointers?

 

[Norcon]

Don't think you need to worry about axial load.
If its just supporting the roof structure then its plenty big enough IMO.

At a guess I reckon it would be good for swl of 4 ton. Probably buckle under 20 ton.

 

[freddiemercurystwin]

-Any pointers?

Employ an engineer?

 

[Shytalkz]

It will **** it.

d/t is the overall depth/flange thickness btw - related to bending stresses, not axial loading.

 

[skyblob]

Thanks Norcon, Shytalkz "It will p**s it" Indeed yes it will, based on the very sound "Thats a damn great bit of steel" approach which I like a lot.

But my BCO still wants the calcs!

Any freebie Javascript type of calculators out there, or tables something like Trada timber - but for steel columns?

 

[jeds]

You've probably got one of those BIs that has been sent out to learn about building work on the job. Just tell him you've consulted a structeng who confirms, by inspection, that it will p*ss it. Tell him this is an approved SE method and is widely taught in Uni's around the country. (well the good ones anyway)