effect of new oppenings on existing wall + slab

[gmd255]

Making new oppenings in existing masonry. Above is RC wall/parapet and a slab.
Do making new oppenings affect parapet (200/1500 mm) in any way?

Because of new oppenings I think that horiz. forces (wind) on the parapet affects existing slab, but not a parapet. Parapet is a cantilever and bending moments at the base of parapet transfer to a slab since parapet is fixed into the slab right?
What Id like to know is does existing design conditions of parapet change because of new openings below a parapet?
Im afraid that becuase of that there may be a need for additional reinforcement (anchors from parapet to a slab).

When it comes to verical loading, parapet now acts as a deep beam, so I dont think there will be a problem since it is 1,5 m high.

 

[SteynvW]

It depends of the size of the openings, if it is small openings then it will not really affect the parapet, if the openings are relatively big then the parapet will start acting as a upstand beam and should just be checked for bending then.

 

[SteynvW]

1.5m is quite deep, even if it is nominally reinforced it should be able to span quite a distance.

 

[gmd255]

Openings are 1 m and 1,7 m wide.

So anchoring reinforcement parapet - slab is not affected by making new oppenings at all ?

 

[KootK]

You'll be asking the slab to hang from the parapet in a way that it wasn't before. The existing detailing may or may not support that. Either way, it's likely fine over such a modest span.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[JAE]

Forget the parapet - probably not a problem.

But do those new wall openings significantly decrease any lateral shear wall behavior of the walls themselves?



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