Ties Spacing / transverse Reinforcement in Piles

[x5bulldog]

I have a question about the tie spacing / transverse reinforcment in piles. I am in a low seismic Region so chapter 21 of the ACI 318 does not apply to me. Also ACI 318 states in chapter 1, that ACI 318 is not for piles unless for high seismic regions.

From ACI 543 in the Structural Design Considerations Chapter that "PILES THAT HAVE SIGNIFICANT BENDING MOMENTS WILL OFTEN HAVE SIGNIFICANT SHEAR FORCES" Chapter 11 from ACI 318 should be followed when designing shear Reinforcement.

What is SIGNIFICANT? Spacing limits for shear reinforcement is d/2 ; that seems intense to me for a pile. With the loadings I have on my piles the Concrete strength (Vc/2) can almost take all the shear. I can be less conservative and reduce my shear.

Again what is significant 5 kips, 25 kips, 50 kips of shear??

Someone can argue that 1 kip or 2 kips of shear is significant and that I have a significant bending member and must use d/2 for my tie spacing.

 

[hokie66]

Piles are normally columns, and should have ties in accordance with column requirements. If they are subject to bending, they are then beam/columns, and should have stirrups in accordance with beam requirements.

 

[x5bulldog]

Again ACI 318 does not govern pile design according to Chapter 1 unless in high Seismic regions. ACI 543 mentions significant Bending moment and significant shear forces.

 

[x5bulldog]

Thanks, I did some more further reading in the ACI 318. The Commentary expands on the topic that the ACI 543 is a Recommendation. It also touches-on that pile desing is regulated by the general building code fully embedded in the ground.

The ACI 543 references back to ACI 318

 

[DST148]

@x5bulldog> What type of pile is it? Typically cast-in-place piles not enclosed by a structural steel pipe or tube are reinforced when subjected to uplift or where the required moment strength exceeds the design cracking moment of the pile. The same logic may be extended for shear design.