I am not sure what you mean, but we usally set bar joists on a brick ledge turned to the inside.

If you are going to finish the wall below the floor we use a taper topped block or a double taper topped block. Set them (the bar joist) on the concrete and use tapcons to anchor them to the wall. Pour our floor and continue upwards.

ICF Contractor

I am using bar joists in my ICF home.  I come up with the idea of using 1/8" steel square tubing that will be embedded in the wall before the pour.  The tubing will be large enough to fit the "shoe" of the bar joist inside it with about 1/2" of movement in either direction to adjust them.  Also the tubing will be spot welded to the horizontal #5 rebar that is running through the wall to help hold the tube in place during the pour.  Once the wall has been poured and the concrete has set up.  I will slide the bar joist into the tube, adjust the height and centers and then tack weld the joist to the tube and then weld it to the steel beam on the other end.  Then I will lay down the steel decking and tack weld it to the bar joist.

My question to everyone out there is, how can I attach my bracing for the 1st floor.  I will have radiant tubing in the concrete so I don't want to pour and then screw into the floor.

Any suggestions would be great.