Stud Rail Layout

[spaseur]

I would like to get your opinions on the following stud rail layout. The column is oriented 45 degrees to the normal layout of the typical columns - see attachment. As I read the code, the rails are supposed to perpendicular to the face of the column. The structure is a post-tensioned slab. If I orient the stud rails to the face of the column, the placement of the tendons and top steel will be difficult to thread through the stud rails. What is your opinion of placing the stud rails parallel to the reinforcing and tendons. In the layout, I have some stud rails parallel to reinforcing and some perpendicular to the edge of the column.

 

[KootK]

As I read the code, the rails are supposed to perpendicular to the face of the column.

Where exactly did you read that? My understanding is that radial stud rail layouts have been shown to be somewhat superior to orthogonal layouts and are sometimes details that way outside of north America.

If I orient the stud rails to the face of the column, the placement of the tendons and top steel will be difficult to thread through the stud rails.

I agree with your concern regarding constructability issues. Any chance you could just have a capital or drop panel at this location to deal with punching shear? Obviously, that screws up the usual desire to have simple, flat plate formwork.

Unless things are very congested, I suspect that your tendons could often be woven through the studs successfully. I probably wouldn't bother with the rails that you show oriented vertically as I suspect that they won't be very effective.

 

[Luceid]

Interesting case. Definitely agree with KootK that dropping the vertical rails shouldn't impact your punching perimeter much, if at all, since you are at the slab edge.