Thanks, PanamaStrEng, There are no signs of settlement, etc., but borings data & bearing capacity equations indicate overload. Also, it doesn't seem kosher to leave that overload in a building that is undergoing extensive renovations. The owner has been kept in the loop and is against the...
There are no drawings, but I had some test pits dug and checked those 2 problems. The footings don't seem to vary with the number of stories supported and the overstress is as described in the original post. Thanks, kslee100, for your input.
The borings show that the footings are on sand, so, unfortunately, the bearing capacity cannot benefit from any time dependent effects. Thanks for your input.
An existing building has 3 levels of continuous beams. Every other column originally terminated at the first floor, but those short columns were extended to the roof to eliminate beam overstress. Foundations for the system of columns and beams have generally benefited from the column extensions...