I did something similar 10 years ago.....

Footings to my garage are a metre wider than the garage (raft foundation).
My new block built shed was to be roughly 8' wide so needed footings that
reached beyond the scope of the garage foundations.
I got two great lengths of angle iron, bent them into large V shaps and
bolted them to the side of the footings.
Then I poured the concrete - angle iron was then submerged in concrete.
OK, no 45 degree thing going on, but that new groundwork has never moved a
milimeter in 10 years.

Hope that helps

Regards
Paul



"The Natural Philosopher" wrote in message
...
robgraham wrote:
I'm adding a shed on the side of my garage.

It works out that the new concrete floor level will just nicely line up
with the top of one of the existing concrete steps into the garage -
makes a nice reference point for the levelling.

However the existing step has quite a 45 deg. bevel on it's leading
edge. Do I need to treat this in any way to get the new concrete to
bond to it ? My concern is that if the bond isn't reasonable, the new
concrete will break away in time as it is potentially a weak spot.

Thanks

Rob

Its never a bad idea to chisel some slots and install some sort of metal
ties in.