Post Baseplate Hold Down 2

[asixth]

Hi guys,

I have a situation where there is a 160mm (6.5") thick slab with a post baseplate sitting in a 70mm (3") recess. I need a minimum of 110mm (4.5") embedment for the anchors which isn't possible, so my options are to either provide:

1) A backing plate on the underside of the slab, visible in the carpark under which the architect doesn't like or

2) Thicken the slab locally around the column baseplate. The slab is post-tensioned.

Which of the two options mentioned above would be the best solution from a constructability point of view?

 

[apsix]

I agree.
It's just as easy (or difficult) to accurately locate the cast-in plate as the recess, but it's easier to hold the plate in place than form up the recess.

Accurately locating any cast-in anchors (if used) is an extra degree or three more difficult.

No one will thank you for spoiling flat slab formwork with a downstand thickening.

 

[kslee1000]

I wouldn't rely on compressive stress from PT for concentrate load, especially at where exists abrupt geometry changes, in which stress could be non-uniform and highly unpredicable (locally). Add some shear friction reinforcement as suggested by others. I will also consider adding some diagonal bars at the corners of the recess.