AASHTO LRFD question

[broekie]

Is anyone familiar with Section 5.14.1.4.2 in the AASHTO LRFD code? Bascially the code says that longitudinal reinforcement that contributes to making a precast girder continuous over a pier should be anchored in regions of the slab that can be shown to be crack-free at strength limit states. I am trying to figure out how to apply this.

How I interpret it is this way - Calculate the negative cracking moment in the deck for the precast girder and deck acting compositely. Compare this moment to the worst case composite negative moments (from live load, barrier, and future wearing surface). See where those 2 moments are equal. The deck reinforcing in the slab that contributes to making the girder continuous has to extend past this point.

It seems like a bit of a weird statement becasue you are comparing something that is associated with serviceability (cracking moment) with strength limit states (factored loads). Any input or experience that others have with this would be appreciated. Books and design examples that I have don't talk about this at all.

 

[Dinosaur]

This sounds like the bar cut-off criteria in three specific statements of the former code, Chapter 8. I don't recall the specific articles. The statements say the bars may not be cut-off less than 12 inches past the point where they are no longer needed, and stuff like that.