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philliosmaximus
5th December 2010, 08:18 AM
Can any designer on here tell me why they would prefer to use steel Ladder beams in their designs as opposed to Ali beams ? :wondering:

I can only think of one reason " the headroom wouldn't allow you "

jakdan
5th December 2010, 08:45 AM
because they are not lifting them:nuts:

scaffy
5th December 2010, 09:33 AM
phillius i can tell you all about this , we scrapped all ours years ago along with unit beams , i think its because ally deflects and steel doesnt , we have managed to change some ladder beam work for x beams in the past , ladder beams are a nitemare to source over 3m long we are doing a job in the city and i have had to get 70 x 4.6m ladder beams toured the country only managed to find 30 had to buy the rest of them new at 80 quid a pop then butcher them to size , oh well got another one going up at the min and need 90m of ladder beam so if you know where there any lurking let me know

ChrisEng
5th December 2010, 09:57 AM
Hi

The main reason I use ladder beams is for jobs where an Ali beam will not fit due to either the length or depth of the location.

Generally for pavment gantries or restricted hieght cantilevers.

Ali beams are too expensive to cut and loose their strength when the end is cut off.

Chris Eng

philliosmaximus
5th December 2010, 10:02 AM
phillius i can tell you all about this , we scrapped all ours years ago along with unit beams , i think its because ally deflects and steel doesnt , we have managed to change some ladder beam work for x beams in the past , ladder beams are a nitemare to source over 3m long we are doing a job in the city and i have had to get 70 x 4.6m ladder beams toured the country only managed to find 30 had to buy the rest of them new at 80 quid a pop then butcher them to size , oh well got another one going up at the min and need 90m of ladder beam so if you know where there any lurking let me
know

But surely thats why we have to put so many braces and stiffeners into the beam work to stop them deflecting and i was always told that ali beams are stronger then ladder beams because of the braces in them :unsure:

scaffy
5th December 2010, 10:06 AM
Thats a question Chris Eng can answer , i thought it was deflection mate to be honest , i know that X beams are stronger tho so they say !!

philliosmaximus
5th December 2010, 10:10 AM
yer i can see why x beams are stronger because of their depth and cross bracing

i was always under the impression that ladder beams where the weakest choice then 450 ali beams , then unit beams , then x beams
(now confused :wondering:)

ChrisEng
5th December 2010, 10:22 AM
Hi Phillisomaximus

You are generally correct, but ladder beams area better in shear than 450 Ali beams and so are better under heavy load situations.

Ladder beams also deflect less than 400/ 450mm Ali beams due to the steel material.

Hope this helps

philliosmaximus
5th December 2010, 10:24 AM
Thanks Chris i didnt know that :)

scaffy
5th December 2010, 10:31 AM
see told you it was about deflection :)

philliosmaximus
5th December 2010, 10:34 AM
HAHAHA i weighed in 75 X 21 steel ladder beams on Friday scaffy

scaffy
5th December 2010, 10:35 AM
hope your jesting me

philliosmaximus
5th December 2010, 10:37 AM
iam mate :laugh::laugh::laugh::laugh: