ACI Appendix D

[hdp321]

I hope someone can help me fully understand the requirements of ACI Appendix D.

I'm having difficulty determining if I should be analyzing my cast-in-place bolts for the baseplate using a "cracked" section analysis, which would apply the reductions to meet the requirements of Appendix D. My controlling load is a 0.9D+1.6WL case. I was under the impression that your section only needs to be analyzed as cracked when checking seismic load cases. I normally always apply the restrictions, but in the case I would be extremely over designing the connection and I also would like to the proper code interpretation.

Thanks

 

[racookpe1978]

So, when the concrete does crack, what will happen to your loads?

 

[WARose]

Analysis can tell you whether or not it will crack……but since just about everything we design eventually will crack (one way or the other) I’ve always treated it like cracked concrete.

 

[Lion06]

Concrete cracks. I don't ever assume uncracked concrete. The only time I might be willing to do that is if I have an embed plate in the top of a beam at mispan or at midheight of a column. There may be a couple other conditions that I'm not thinking of, but I would only do that if I really needed to. I don't ever start assuming uncracked concrete.

 

[steellion]

Agreed with Lion06.