Check for transfer of horizontal forces by shear friction (pad and strip base:ACI 318)
This check applies when a concrete column is attached to the foundation.
Determinate if the shear-friction design method applicable1: When surface is not intentionally roughened (conservative assumption) |
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If | |||
Vu | ≤ | Φshear * Ac min(0.2*f’c , 800psi) | for US units |
Vu | ≤ | Φshear * Ac min(0.2*f’c , 5.5MPa) | for metric units |
where |
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Vu | = | max[abs(Fy,sup,u) , abs(Fx,sup,u)] | |
Then maximum shear transfer is permitted at the base of the column. |
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Required area of dowel reinforcement: | |||
Avf | = | Vu / (fy * Φshear*μ) | |
where | |||
μ | = |
0.6 |
when concrete not intentionally roughened (assumption) |
μ | = | 1.4 | when concrete placed monolithically |
Currently dowel bars are not designed. The area of the provided column reinforcement As,prov,column is the same as the provided reinforcement of starter/dowel bars. |
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If | |||
Avf | > | As,prov,column | |
Then check fails |
Footnotes
1 ACI 318-08 Section
15.8.2.1