corner rf in concrete wall

huangyhg

corner r/f in concrete wall
which of the two (a or b) is the correct way to detail the interior horizontal bars of a concrete corner/ intersection?  assume that the walls are exposed to lateral on both sides.
i've uploaded a pdf -- corner_rf.pdf
thanks
always have done in like 'a'.  
either is acceptable, but i never use the diagonal bars.
daveatkins
i agree with dave. would only need diagonal if there was a problem with development length for hooks. i haven't used a diagonal before either.
of the two details, i would use "b", and i use diagonal bars for liquid retaining structures.
i don't think the direction of the hook is important to developing the hook.

thats right. i normally show the hooks like b but the direction doesn't matter in my opinion. i guess if the tail is long enough it will dictate the direction.
doesn't matter at intersections, but i have always used "a" as a typical detail at corners.  often, the wall thickness is not sufficent to allow placement of standard 90 degree cogs within the wall width at corners.  but if any of the corner joints are opening joints and are supposed to carry a lot of moment, neither detail is actually very efficient because there is no reinforcing to resist diagonal cracking.  think of the truss analogy, and without diagonal reinforcement from outside to inside corner, the compressive force cannot go around the corner.  hairpins in both directions have been shown by european testing to be best for opening joints, and i think double hairpin corners is common practice there in highly loaded joints.
any comments on the attached detial?  it uses hairpins and eliminates the exterior l bar from type b above.
i re  
the diagonal bars will blow out your interior corners if they ever go into tension. the vector addition of the two directions of the bar points right into the corner. we always put the bars as far from the corners as possible.