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I need to supply some design curves

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geo0987

Geotechnical
Aug 17, 2017
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I need to supply some design curves to a structural engineer on cast in place pile foundations. I have drilled the site and collected soil data and ran the tests and provided recommendations for skin friction, active, passive, end bearing capacity, etc. I would assume 0.5% steel in the pile does anybody know what curves this would be??
 
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That last sentence is not usually something a geotech provides, since it is structural. Heck, he may decide to use pipe piles or timber, who knows.
 
OG has it... leave any reinforcing of the pile to the structural guy... You have no idea of any moment or whatever applied to the top of the pile.

Dik
 
Cast in place piles, so I assume straight shaft bored piles, rather than belled piles, or driven expanded base cast in place piles like Frankipiles. If my assumption is correct, end bearing capacity for different sizes at different founding levels would be needed. If the same recommended pressure regardless of size, then the design bearing pressure at the different levels would suffice. Skin friction values should show how they vary over the height.

Not sure how active pressure values apply to bored pile design, but recommendations for lateral design would include passive pressure at the different levels.

Be sure to clearly state whether your recommended values are based on working or factored loads.
 
Not enough information has been provided but I assume the requested curves are the shear and moment curves that can be developed using LPile or AllPile. Geotechs often provide these curves to the structural engineer for use in designing the foundation piles.

 
I think that the curves are for lateral design. Perhaps, curves as PEinc suggested. Or perhaps, lateral capacity vs. head displacement for different reinforcement ratios and pile sizes.
 
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