New strip footing near existing strip footing

[GalileoG]

Hi all,

I am designing an expansion to an existing two-storey building (see the attached sketch). The new structure consists of steel beams and columns. I also need a non-load bearing block wall (for fire separation) between the two structures.

The columns and block wall need to be as close as possible to the existing wall. Need some ideas on how to design the foundation to avoid any impact to the existing footing and for the new footing to be able to take the eccentric load. The strip footing as shown does not work for the eccentric load. I would like to keep the new footing structurally separated from the existing footing. Any ideas?

If I am able to move the columns away from the existing wall, but keep the masonry wall where it is, would masons have enough access to place 3 courses deep behind the steel beam (between steel beam and existing concrete wall) at the second floor and roof?

Your input would be much appreciated.

 

[KootK]

Some permutation of a strap footing might suit your foundation system. Search for that here and you'll find plenty of information. I'm not sure that I understand the situation well enough to comment on the block behind beam part as I can't discern the beam in your sketch.

 

[gte447f]

Perhaps you could pull your new foundation wall away from the existing foundation wall far enough to eliminate the eccentricity on the new footing, and use a thicker concrete slab that could cantilever a short distance over the new foundation wall to support the new masonry wall?