Steel Plate on top of Concrete Column?

[Hydrostru]

Can I have a steel plate with welded studs on top of a concrete column? The plate will be larger than the concrete column section. I have concern about how the contractor places and vibrates the concrete. Or they could insert the plate after concrete pouring and vibrating? Please advise. Thanks.

 

[madmantrapper]

I have placed steel plates on top of concrete columns after the concrete was poured in the tube and vibrated. Fill to capacity and place plate, rattle the place to be sure the concrete is filled in around the studs. Just because I have done this does not mean it is right but it seemed to work.

 

[yaschief]

Another method that I have used is to have a hole in the center of the plate that would allow additional concrete to be placed (if the column form was not filled completely) or to allow excess concrete to exit the top of the column form during vibration.

As to vibration, unless it is a steel form, I would not vibrate the form as the Sonotube type forms can deform/collapse after being filled with concrete and then vibrated via contact with the side of the form by the vibrator.

Vibrating or "rattling" the plate is an accepted method of achieving the goal of properly anchoring the plate studs into the concrete.

 

[Duwe6]

You could treat the plate like a pump baseplate: Place several 1/2" - 1" holes in low stress areas, for air to escape the pour. Then have someone witness the pour and make sure that 'paste' exudes from all of these holes.

 

[robyengIT]

for the last 2-3 cm (1-1.5 inch)I was used to pour grouting mortar that can expand (increase in volume) so to be sure that the steel plate is laying on concrete
cheers

 

[Hydrostru]

Thank you guys. Drilling holes for the air & concrete to escape sounds a good idea. I am going to look into it. Thanks again.