Nothing to do with landies

[tony]

G'Day All

Are there any structural engineers on the site?

I want to spand nine metres supported at each end, what size bit of steel do I need to carry about half a tonne.

[dobbo]

like an engine hoist?

[p38arover]

What sort of span do you want?

Straight truss, arched truss, if arched, how high can it be?, a gable roof truss - I don't know the architectural names, just thinking aloud about possible designs.

More detail required.

Ron

[barney]

probably a straight "I" beam so that he can run a chain hoist on a carriage

[tony]

Nope wanna put a floor in arf the shed,but dont wont to have poles in the middle of the floor so i would guess an I beam that would span the 9 m then run beares off them and the floor on top

[dobbo]

Two channel beams bolted back to back to form an I section (like on the Ranbuild sheds) lighter weight

[one_iota]

9m is a big span :eek: for any material: steel, timber or concrete

And it depends on a lot of things: Like the imposed live loads and the dead loads.

You need some detailed professional advice.

I work in the industry.

"Not so squeezy"

[tony]

9m is a big span :eek: for any material: steel, timber or concrete

dead loads.

You need some detailed professional advice.

I work in the industry.

"Not so squeezy"

So when you wanna come over for a beer, :)

dead loads.................mate I aint gonna av anything dead in there

[mark2]

The only cost effective way to make a mezzanine level in most sheds with a 9m span is to use 1 central post or preferably 2 posts @3m to suppport the bearer. For this a C200 will suffice. If your shed portal frames have some strength ie they are hot rolled sections or trussed members, you may get away with using a vertical tension member from the center of the beam to the apex joint in the portal frame.
Most sheds these days use lighter and cheaper cold formed sections and it just isnt practical/safe to span 9m and rely on this type of frame to carry the vertical loads and bending moment which will be induced in the columns. Also, any beam capable of spanning 9m AND supporting a floor load is going to be expensive and heavy.

[tony]

The only cost effective option in most sheds is to use 1 central post or preferably 2 posts @3m. For this a C200 will suffice. If your shed portal frames have some strength ie they are hot rolled sections or trussed members, you may get away with using a vertical tension member from the center of the beam to the apex joint in the portal frame.
Most sheds these days use lighter and cheaper cold formed sections and it just isnt practical/safe to span 9m without at least one support to ground level.


Mark
the portal frames i think are trussed 50mmx50mm box so are strong I think and I wz gonna support the cross beem from the center of the frame apex as I dont wont to clutter the floor but trying to find out what beem to use is bloody hard

[mark2]

Sounds like the apex joint could be used as a support - effective span will only be 4.5 if hanging from the portal apex.
Depending on your/mates welding skills it may be worth welding up a trussed beam about 300 deep using 50mm RHS with chords at 60 degrees - can be done in a few hours by a good welder. - Other options are a cold rolled C200/250 (cheap but will have some bounce) and use top hats @ 450 for joists. Otherwise use a hot rolled section but is a lot pricier and heavier.

[tony]

Sounds like the apex joint could be used as a support - effective span will only be 4.5 if hanging from the portal apex.
Depending on your/mates welding skills it may be worth welding up a trussed beam about 300 deep using 50mm RHS with chords at 60 degrees - can be done in a few hours by a good welder. - Other options are a cold rolled C200/250 (cheap but will have some bounce) and use top hats @ 450 for joists. Otherwise use a hot rolled section but is a lot pricier and heavier.


Mate my welding is preety good if I had any idia what a "chords" was

I like the sound of the C200/250 (cheap) so if i used the C250 supported at the ends and from the apex how much bounce do you think it would have and how far apart could they be

Dont live in sydney do yea

[51jay]

Save yourself some grief......Pay a pro to come on site and advise you. Cheap is ok..but not if it comes down on someones head

[p38arover]

9m is a big span :eek: for any material: steel, timber or concrete

'Zackly, which is why I didn't suggest an I-beam.

See Wide Span Sheds - they do up to 9 metres http://www.sheds.com.au/New-Pages/FarmSheds.htm


Years ago, my father designed and built a machine to bend round steel bar to a zig-zag shape to make trusses for one of the larger chicken companies for their sheds in Sydney. One can get long spans with those - but they weren't flat, each span consisted of two trusses bolted together in an apex. They are called open web steel joists

http://www.epcserver.com/graphics/SteelJoistK.gif
Ron

[tony]

'Zackly, which is why I didn't suggest an I-beam.


each span consisted of two trusses bolted together in an apex. They are called open web steel joists

Thats what holds the shed up, I need a something to span between them to put a floor on without losing too much head room from the floor to the roof and also off the ground floor to the mezzanine and keeping a clear ground floor, the shed is 3 bays long the mezzanine will cover two end bays and a hoist in the last bay

T

[p38arover]

Is there any reason you can't use the same sort of truss? A 9 metre span might need a deep truss which could be your problem.

Ron

[tony]

Is there any reason you can't use the same sort of truss? A 9 metre span might need a deep truss which could be your problem.

Ron

Yer Ron I did think of that after reading your other post but I would other lose head room to the roof or head room to the mezzanine floor which is something I wont to keep to a max in both spots

T