Concrete topping reinforcement
Concrete topping reinforcement
(OP)
I’m working on the design of a single span adjacent prestressed concrete box beam bridge with a composite concrete topping/deck and I’d like to know if there are any procedures to calculate the amount of transverse and horizontal reinforcement needed in the topping. Or do you just provide temperature and shrinkage reinforcement in each direction?
In the transverse direction the box beams will be post-tensioned together, but I’m still worried about longitudinal cracks developing in the deck. I may just provide heavier reinforcement in the transverse direction, say #5 @ 9” or 6”, if there’s no way to calculate a required reinforcement in that direction. The deck may crack in that direction anyway regardless of the reinforcement provided just because of the joints between the beams. Let me know what you all think.
Thanks.
In the transverse direction the box beams will be post-tensioned together, but I’m still worried about longitudinal cracks developing in the deck. I may just provide heavier reinforcement in the transverse direction, say #5 @ 9” or 6”, if there’s no way to calculate a required reinforcement in that direction. The deck may crack in that direction anyway regardless of the reinforcement provided just because of the joints between the beams. Let me know what you all think.
Thanks.





RE: Concrete topping reinforcement
ftp://imgs.ebuild.com/woc/C890023.pdf
www.SlideRuleEra.net
RE: Concrete topping reinforcement
I have no idea how those numbers were developed and suspect that no one at MDOT would be able to tell me either. Just the way it has always been done.
RE: Concrete topping reinforcement
Broekie – I will basically be going with the reinforcement you have mentioned. This bridge project is actually a county job in Michigan so we’re following MDOT standards for the most part. Also, the reinforcement you mention is what we have used on similar past projects. Once the snow clears and I have some free time I plan to visit some of these bridges to see how they are performing.
SlideRuleEra – Interesting article. I noticed at the end it was published in 1989. Is that true? I haven’t heard of this philosophy catching on in the states.
RE: Concrete topping reinforcement
that's interesting I don't think I've ever specified a #3 bar. What will the crazy dots think of next?
RE: Concrete topping reinforcement
www.SlideRuleEra.net