Fixing steel columns into concrete, stud length...

[Deluks]

What are general* lengths and M size for fixings that hold up steel columns (UC's)

I have four columns to fix into a concrete pad. (not sure of pad depth yet but no less than 750mm)

Each one will be supporting about 500kg max.

Which is the better method of fixing.
concrete in with the pour, grout in afterwards or resin?




*I know there is no straight answer but if anyone has experience with column fixing then some pointers would be appreciated.

 

[^woody^]

It will depend on what the columns are supporting, and their section size

If there is likely to be some lateral movement, and/or the columns are wide, then you want deeper and built into the concrete. Probably m12's

If the bolts are just basically holding the columns upright, and/or the columns are narrow, then you may only need some expansive bolts drilled in afterwards - m10's should be fine

 

[noseall]

i thought a u.c. would require an independent foundation.

doesn't the slab get laid later on and around the columns?

 

[Robert too]

The bolt size will depend on the frame size / height and the base plate size .

I would get the engineer who designed the frame to give you this info , he has most likely just ommitted to supply you with all the info .

 

[Deluks]

4 will be used in conjunction with a block wall to hold up single storey garage roof. I'm suprised you suggest M10/M12, I would've thought they would be underspecced for any application like this. Not knowing the science behind it, but it sounds like gravity does the main work, and the studs just stop the structure from 'sliding about'

Having said that there are M12 sized holes drilled in the baseplate, which themselves are about 220x250. Column 2.5m high.

The 4" slab is already there. I need to cut a hole in it, dig down and pour a deeper pad.

So length of stud? I've been looking at M16 190mm resin fix But maybe I should get pack of M12 threaded rod from SFix and use suspended formwork when pouring the pad. Does 500mm depth sound like overkill?

 

[^woody^]

If the columns are acting together with a supporting wall, I can't see where the shear stress will come from to require an m16 bolt

And I can't see why the fixing needs to be more than 100-150mm if there are no significant forces trying to rotate the column and lift the base upwards

If the wall is tied to the column too, then it really is not going anywhere.

Your biggest problem is making sure the pad is sufficient to transfer the load from the column to sufficinetly wide area and deep bearing soil, and also if it needs any re-bars to deal with any punching shear

Was this structure designed or are you improvising?

 

[Deluks]

The bolt size will depend on the frame size / height and the base plate size .

I would get the engineer who designed the frame to give you this info , he has most likely just ommitted to supply you with all the info .

Self engineered Detached garage roof, I'm basically gathering as much data as I can and over-engineering from there.