Sawcuts in Stiffened RC slabs

[civeng80]

I wonder if sawcuts are used or permitted in reinforced concrete slabs with stiffening beams.

Reason Im asking is that part of my slab on ground is floating slab i.e. no stiffening beams so sawcuts are to be used and a part is stiffened to allow for extra load, but then can I space the sawcuts evenly so that it also covers the stiffened slab ?

 

[KootK]

While I don't think that it's a huge deal either way, I vote for not saw-cutting. Here's why:

1) the saw cuts reduce your effective flexural depth a bit.
2) saw cuts will be much less effective with continuous stiffening ribs thrown into the mix.
3) not having saw cuts saves money.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[rowingengineer]

Depends on finish, use, type of stiffening beams ect, but for commercial polished floors with stiffening beams below hte slab, I would specify them and try to keep the size of pours to a good size. for integral beams and covered situations I would not.

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[KootK]

I just assumed that the stiffening beams would be integral with the slab. Is that not the case?

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[civeng80]

Stiffening beams are integral with slab.
The problem is we want to pour the stiffened slab together with the floating slab (without beams) all together.
Then we have to sawcut the floating slab but to get regular sawcuts it would also continue on to the stiffened slab.

If it didn't sawcut would finish abruptly and that would look weird.

 

[hokie66]

I don't think there is a general rule. If you would post a plan, perhaps we could give some opinions as to where to sawcut or not.

 

[KootK]

If you want the saw cuts for aesthetic reasons, I don't see any harm in it.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[JAE]

Seems like the stiffened slab portion should be separated from the floating slab...the two are going to behave very different.

I've never sawcut a stiffened slab before as it is not necessary.


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