Core wall modifications
Work has progressed significantly on site now. We have poured the basement slab, got the pre-cast walls to ground level installed, poured the internal core walls to basement level and completed the first pour of the ground floor slab. By the end of this month we should hopefully be well and truly out of the ground.
We have encountered quite a major issue on site during the last 24 hours with the external core walls. The wall was designed very close to its capacity with the strength being increased from 80MPa to 100MPa to make it work. The subcontractor responsible for the core capping beam has installed the starter bars for the walls 100-150mm out of position thereby reducing the effective depth of the wall by close to 10% as well as its capacity. This reduction in effective depth has tipped the wall over the edge and it no longer has the capacity to take the compression forces in the corner – the forces modelled are >150MN.
So what? The wall has been modelled and designed as a wall but due to the nature of the forces it must now be designed as a column which means compression ties. This will be fun when your wall currently looks like this….
Holdfast Training Services Trial Blog 
If this wall is acting in compression or tension then the Area steel provided is as per design and OK as is Ac, the only real concern in having the steel out of position is surely it’s capacity in bending out of plane, which is not a usual design orientation for a wall? Are you sure your bursting forces are going to rise so significantly that this will need ties? Surely the bursting forces are the same as they would have been for the wall in it’s intended form? Generally to change from a wall to a column requires a change in geometry. What exactly is the steel doing in this instance?