Placing column footing next to existing wall--foundation

[Qwikone]

I have an existing wall with concrete footer/foundation at 30" deep. I need to place a column supporting a girder truss adjacent to the existing foundation, the problem is that I need to get the column as close to the wall (6"-12") as possible. The existing footer is 24" wide with 8" block in the center. The column footing requires a 30" width. I looked at an eccentric condition and the placement of the column on the end of the new footing but I'm concerned the loading will impinge on the existing footing. I also looked at step pouring the new foundation over a portion of the existing to obtain the 6"-12" distance........
Anyone have experience or suggestions with this?

 

[msquared48]

Underpin the new footing under the existing strip footing as needed.

Mike McCann
MMC Engineering

 

[Qwikone]

Mike-
Thank you for such a quick response!!
That will work nicely......
Qwik

 

[dik]

Make sure there are no lateral loads on the wall from the vertical load.

Dik

 

[XR250]

What MSquared said unless the loads are relatively small.

 

[KootK]

If you've got a contractor on board, I'd recommend consulting them. A colleague specified a solution like Mike's a couple of weeks ago and our contractor objected to it pretty strongly. We ended up going with an eccentric pad footing with a strap beam over it tied down at the far end with a screw pile. Of course, screw piles are ridiculously cheap in my are due to the character of our soils and the quantity of industrial work that happens here.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[Qwikone]

Thanks for all the great replies!!
I am proceeding with underpinning the existing wall (light loads--non-bearing walls above it) placing the column footing below and underpinning a portion of the existing footing. This gets me the minimum offset of the column, with minimal impact to the existing wall/footing.
I do have the contractor on board, and he agrees that this was the most economical and quickest solution compared with the other alternatives presented............
Qwik