Enlarge Existing Footings-Part 2
Enlarge Existing Footings-Part 2
(OP)
This is a followup to a previous post a couple of months ago. The problem is to enlarge existing footings in place to support the addition of two new floors without underpinning (due to spacial constraints).
After running numbers on punching shear the existing footings fail under the increased load. There is room to pour on top of the existing footing. Has anyone had experience with this and how to best transfer shear to upper slab? I was thinking about welding angles to column.
After running numbers on punching shear the existing footings fail under the increased load. There is room to pour on top of the existing footing. Has anyone had experience with this and how to best transfer shear to upper slab? I was thinking about welding angles to column.






RE: Enlarge Existing Footings-Part 2
RE: Enlarge Existing Footings-Part 2
RE: Enlarge Existing Footings-Part 2
RE: Enlarge Existing Footings-Part 2
RE: Enlarge Existing Footings-Part 2
The possible approaches would be to widen the column bearing to reduce the punching stress as suggested or shore the column up and pour a new footing.
RE: Enlarge Existing Footings-Part 2
Are you sure that you can't use micropiles to add capacity instead of enlarging the footing?
Jeff
RE: Enlarge Existing Footings-Part 2
RE: Enlarge Existing Footings-Part 2
RE: Enlarge Existing Footings-Part 2
I just meant that adding capacity though piers or micropiles connected to the existing footing might cause less disturbance and proceed faster than enlarging the footing.
Many micropile contractors can work in low headroom conditions, if that is the major reason for not using an underpinning method.
Good luck with your project.
Jeff
RE: Enlarge Existing Footings-Part 2
If you have a pedestal (pier) then you have a great deal more options.
RE: Enlarge Existing Footings-Part 2