length development for hook dowels vs. punching shear for footing thickness

[33mmrrdd]

I just noticed that the footing thickness required for length development for hook in tension is sometimes so much higher than the required thickness based from punching shear.

Is this really reasonable?

PCA Notes example problem shows that we need to consider length development in tension when the footing is subjected to horizontal force, checking the shear (transfer) friction between the top of the footing and the base of the column resulting dowels under tension.

But I realized that is not the only case. When the column is also subjected to bending, column main bars (or dowels) are also in tension.

Any thoughts?

 

[JAE]

Yes, sometimes footing thickness is controlled by the requirements for dowel development.

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[dik]

YOu can use a longer hook length with a reduced thickness of footing for tension... not for compression development... hooks are non effective.

Dik

 

[DaveAtkins]

I disagree with dik. Simply extending the horizontal length of a bar beyond the bend in the hook does not increase development--it does not meet Code.

DaveAtkins