Shear reinforcement for inclined member
Shear reinforcement for inclined member
(OP)
I am currently working on the design of reinforced concrete stairs. The middle landing will be cast as part of the stair, with sets of stairs on each side. The stairs land at an angle to the girders. In this sense, the stair is like a folded plate. My question is how to detail the stirrups over the supports at each end. Will a shear crack develope at 45 degrees with respect to the member axis, or a global axis. Basically, should the stirrups be inclined or perpendicular to the member axis.






RE: Shear reinforcement for inclined member
RE: Shear reinforcement for inclined member
RE: Shear reinforcement for inclined member
As for the reinforcing at this "bend" here is an edited quote from the reference:
"In addition to the main reinforcement ... which is the amount required to resist negative as well as positive moments, 3/8" distributing and spacing bars should be placed above the main reinforcement ... The main bars should be of such lengths as adequately to reinforce all possible regions of tension. This means that the negative reinforcement should extend about one-fourth the distance between supports from each support, and where landings are included in the span, the negative reinforcement should also be carried well into the landing slab, since the stiffness of the landing slab connected to the two inclined flights may cause negative moments in the flights for some distance out from the landings."
I have left out references to tables and diagrams in the text.
There is a lot going on at this transition point and it does need proper attention.
Hope this helps - if you can't find more modern ways to address this situation, I can e-mail you a scan of these pages, just post an address.
RE: Shear reinforcement for inclined member
RE: Shear reinforcement for inclined member
RE: Shear reinforcement for inclined member
And many times the way engineers handled shear back then will not meet current codes or design requirements.
RE: Shear reinforcement for inclined member
RE: Shear reinforcement for inclined member
Nothing like a little engineering adrenalin.
RE: Shear reinforcement for inclined member