Cutting Off 25 % of a Column Footing Projection
Cutting Off 25 % of a Column Footing Projection
(OP)
I am involved with underpinning a corner column footing. In order for the new elevator cab to go past the corner footing, a 36inch x 36inch piece of the footing must be saw-cut off. The new elvator pit slab 5 foot down will now be dowelled into the underpinning pits with chemical anchors to assist as the new( 25%)footing. A NYC structural engineer(EOR) says this is no problem. Has anyone ever seen or done this before?? Your comments will be greatly appreciated.






RE: Cutting Off 25 % of a Column Footing Projection
Engineering is the art of not constructing...of doing that well with one dollar what any bungler can do well with two after a fashion.
RE: Cutting Off 25 % of a Column Footing Projection
The 25% sections of a column footing is the standard procedure,however the footing was 6ft. x 6ft. with a soil allowable bearing capacity value at just around 5,000psf max. Without the inside 25% it goes to 6500psf and thus the need to use the elevator pit slab dowelled to the underpinning. Settlement unknown, since there is no Geo-Tech for the job. Groundwater has become a major issue, so micro-piles may be a last resort.