Rebar Placement

[btv189]

I am currently prepping for a base slab that is 2' 9" thick and the drawing calls for #11 on 9" centers, my question is being that the bars have 90 deg bends for tails on the ends of the #11 for all sides of the slab how do you get the first bar that runs perpendicular to be within the tolerances of 117 for the design location of the first bar (as well as the clear distance to the form work)?

 

[hokie66]

This is best worked out on site with the design engineer. The design engineer should know which of these requirements predominates.

 

[TXStructural]

There is no specific requirement that the bar at the edge be inside the hook, although I suspect that the designer drew it that way and placement considerations make it difficult to do otherwise. Moving the bars inward is a common practice, and is unlikely to result in a reduction of strength. Another solution may be to make the concrete wider (thus increasing its overall dimensions) such that the reinforcement layout is as designed.

Also, hooks are not required to be uniformly-oriented or precisely vertical, and research shows that this is not required to maintain development or flexural integrity. This permits rotation of the hooks to suit placement considerations.