how to calculate crack stress in operating a concrete pile?

[RobertEIT]

Can anybody please tell me how to calculate the crack stress in operating a concrete pile? Is this crack stress equals 6*sqrt(fc')? Say if the concrete compressive strength fc'=6000 psi, the crack stress equals 6*sqrt(6000)=464 psi?

Thanks a lot for your help.

 

[JStructsteel]

Do you want the actual stress, or the threshold for cracking? I would use 5#sqrt*f'c for threshold. ACI may have other for piles

 

[RobertEIT]

Well, I am seeking the NCEES recognized formula, I believe there is only one formula which NCEES accept as the correct answer, My formula comes from Donald P. Coduto's book << Foundation design>>. But I don't know if it is NCEES accepted correct formula. That's the big problem.

 

[JStructsteel]

was this for a test question? I would use what was in ACI or PCI if prestressed, etc. MAybe I am not understanding the question.

 

[RobertEIT]

jrisebo:

I can't find anywhere in ACI or PCI at which crack stress in operating or handling a concrete pile (or prestressed concrete pile) is discussed. All I can find is the discussion of permissible stress at transfer or in serviceability stage etc.