Existing Foundation Wall Load Transfer

[Wheels77PE]

Working on a bearing wall removal project. New column load, 26 kips, will bear on existing 12" wide p.c. foundation wall (load will be applied at inside face of wall). Existing footing will be underpinned with a new spread footing. What type of analysis needs to be preformed to check the load transfer capability of the existing foundation wall? It is 9' tall with some vertical & horizontal #4 bars. New point loads bear on an interior and exterior corner.

 

[milkshakelake]

Need sketch; an engineering sketch is worth a thousand words. But check bearing of steel base plate or concrete column on the wall. Check wall for lateral earth pressure and surcharge because you are increasing the depth. Make sure your underpinning is tied into the existing wall with epoxied dowels, but if not, check for overturning and sliding of the underpinning like it's a retaining wall (I don't like to do that though, but it's just my preference).

I generally assume a 12"x12" concrete pier built into the existing wall for the new column. Check axial loading on the concrete pier, assuming no rebars because you are underpinning. If 12"x12" isn't working, you can add a concrete pier. Check the concrete strength with testing. Definitely check eccentricity of the footing since it's in a corner.

If your new column has uplift or moment, then that's a whole other story. I'd just add a new concrete pier which is designed for that, and it will have a better load path to the new underpinned footing. You can epoxy-dowel the new concrete pier into the existing wall.