Strut and Tie Concrete Beam - Boundary Between B and D Regions

[msegerman]

Hi,

I have a situation where a small portion of my beam is a d region, which has governed my design. This required additional reinforcing such as longitudinal shear reinforcing. Once I'm out of the d region, can I terminate some of this "special" reinforcement?

Please see attached sketch.

 

[asixth]

I don't think shear reinforcement would be required for the D-region and if ties are provided it would be for confinement of the concrete strut. I would continue the top reinforcement (the tie reinforcement) well into the backspan without lapped splicing. There will be some shear throw into the backspan and I think it would be good to have a couple of ties extending back from the face of the column but as you go further into the span I would look to detail only nominal shear reinforcement if possible.