Hello, my understanding of the splitting resistance for slab girders is that the reinforcement used to prevent splitting in the pretensioned anchorage zone is oriented horizontally (third paragraph of AASHTO LRFD 5.9.4.4.1). While reviewing the detailed report for the splitting resistance in my model, I am unable to match the value of As used for calculating the capacity. I am wondering how I can check which legs of the transverse stirrups PGSuper is considering within the splitting zone (only 12"). Maybe I have missed something in my check.
TIA
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The reinforcement is derived from a square inch per foot “smeared” value.
The reinforcement on the resisting side of the equation is computed as
(4 legs)(0.2 sq in)(3” zone)/(3” spacing) + (4 legs)(0.2 sq in)(9” zone)/(12” spacing) = 2.0 sq in
The 3” + 9” zones is the 12” zone length for h/4.
Also see https://www.wsdot.wa.gov/eesc/bridge/software/Documentation/PGSuper/7.0/...
Thanks for your response.
Since the splitting reinforcement for the voided slab is supposed to be the horizontal bars (so top and bottom bars of a closed stirrup) then I would think the calculation would be using 2 legs, not 4 legs. I'm thinking that for this check I will need to uncheck the box "Use primary bars for splitting resistance" and just define the splitting reinforcement as 2 (horizontal) legs of #4 bars spaced at 6" within the first 12".
To match your format above, my understanding is that the calc would be:
(2 legs)(0.2 sq in)(12" zone)/(6" spacing) = 0.8 sq in