Modelling of a floor slab / core wall juntion 1

[hockley]

I'm in the process of modelling a multi-storey building with RC floor slabs and core walls. I'm wondering whether, from the point of view of the design of the reinforcement in the walls, it is unconservative to have a 'hinge' (preventing the transfer of moment from the slab into the walls) in my model at the junction of the slab and walls?

I'd be interested to know how others model this situation - I realise that some moment will in reality be transfered from the slab to the walls - but I suspect that for a 380mm slab and 200mm wall its not going to be as much as my model is predicting (in which everything is continuous).

Any help on this would be gratefully received

 

[dik]

Depending on the detail of the joint at the wall, If the slab runs over the top of the wall, I treat it as monolithic... if a 2x6 key is used, I often treat it as pinned or something less than monolithic (depends on the mood), often 1/2 stiffness. For positive steel, I generally assume the stiffness of the core at 1/2.

At corners of shafts, I treat the slab as fixed and typically add 2-25M (#8) right at the centre of the wall that is parallel to the span, plus the balance based on the tributary width (high stress area)

Dik