cutting a loaded standard (1 Viewer)

Big Gav

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what is the best method of cutting a loaded standard ?

1. transfer the load before hand ?

2, cut loaded standard and let the load go in to beam and then into a standard already carrying a load, using a disk cutter or tube cutter ?

3, insert a extra standard with a screw jack . tighten it up to take the tension. remove the attached members to the standard to be removed.
knock out the sole board and then cut the standard.

4. can you not cut a standard with a load in it ?

advice would be most welcome

many thanks
 
Option 1 would be the easiest in the long term, although they all would probably work eventually.
 
Like phil said - transfer the load to either a beam,spur,pullback etc ....then cut the standard out in a diagnal shampfer cut, knock it out clear & retrim the diagnal cut & cap
 
Transferring an existing load into a beam without the scaffold sagging is easier said than achieved.

To effectively achieve this the beam would need to be pre-deflected. Not gonna happen.

What actually happens is the beam is inserted and then the leg is cut but before the beam is actually working it needs to accept the load through deflection (no matter how small a deflection)

The result is the beam sags under the imposed load and the scaffold above comes with it. In many cases in tall scaffolds the ledgers pick up the greatest part of the load before it gets to the beam.

I saw the beams fail on St Pancras station in the late 70's all the ledgers above deflected and held the scaffold up. NOT TO BE RECOMMENDED as a design strategy though.

If pressed for an answer I would put in pull backs in tension if possible and dependent upon the load imposed I may back that up with a ladder beam.
 
thanks for the reply

The problem I have is that the contractor will transfer the load along a beam .
but the transfer point will be done by the cutter.. with no extra standard inserted. hence diverting the load path in to a already loaded standard ,

my concerns are that any deflection will go direct on to the cutting blade and putting the operative at risk of harm.

i suggested a extra standard placed 300mm in front of the exsiting standard would be a safer methods, but he insist that the calcs add up
He has to insert a safe working platform for the operative to do the cuttings , but why wont he insert the extra standard ?
 
Depending how high up the leg, you could put your beam above the joint, knock the middle out of the sleeve and then remove the leg?
 
Sounds complicated this one , make sure you charge plenty

---------- Post added at 06:19 PM ---------- Previous post was at 06:17 PM ----------

I do love it when a designer talks dirty Alan :laugh::laugh:

Proper old school knocking the centre out of a sleeve ;)
 
:pI think we both know it's not that tricky but has the potential to become so.
I can talk dirty Phil, you just have to pay a little extra:blink1:
 
Hello Mr Reade obviously inserting the beam is the norm , depending on how many standards your beam runs through and then inserting an additional standard next to the standard deemed for the still surely the weight transferred onto the beam and your secondary standard will be very little but calculations creates pounds shilling an pence enjoy your bonus an have a drink an tell the boys to get cracking.scc
 
Why won't he use an extra standard? Best to ask him to explain it. I would guess that the load from the standard which is to be cut is small enough to not overload the standards which are carrying the beam when added to the load already in them. The logic would be that if you don't need a standard in the finished job, there is no need to add it temporarily so perhaps you are talking at crossed purposes.

It is possible and not too difficult to pre deflect a beam by using puncheons and screw jacks to lift the ends after it has been connected to the standard to be cut and before it is fully connected to the supporting standards. You can check that it is being deflected because the load comes off the base plate and you can slide it around.

Using a short length (400mm) of ladder beam across and doubled onto a standard which is to be cut will prevent the saw blade being trapped. Once the cut is made, one of the doubles on the beam can be eased off. The cut needs to be diagonal if the span of the new supporing beam is more than about 3m because deflection will close the gap up and you will have to do it again.
 
Morning SSC,
without knowing more about the scaffold it would not be possible to say if the load transferred to the beam would be large or small but with a typical leg capacity of around 28kN I guess you wouldn't want it on your foot for too long. Inserting the beam is indeed the norm as is inserting the pullback option. The point I was relating is one that is all to frequently overlooked in scaffolding which becomes more of an issue with the increased use of alloy beams which are prone to greater deflection than steel beams.
You are correct calcs do cost money, that said most won't do them until they are asked for.
Stay well
Alan
 
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