point of fixity for a concret pier foundation

[wail123]

how can i calculate the point of fixity for a concrte pier foundation used to support a new house. the pier will need to be embedded at least 5 feet into formational materials with an overall min embedemnt of 10 feet, vertical bearing capacity is 10,000 psf, up to 30,000 psf. 24-inch diamter.

 

[Ron]

Assuming your are referring to the point of fixity relative to a moment on the pier, though most house piers don't have any significant rotation, though the shear load can be large...

The point of fixity is the point at which the earth pressures adequately resist a couple created by the moment or resist the lateral shear, or both. I would go beyond that a bit just because of the variability of soils.

Your bearing capacities seem a bit high. What kind of material are you in?

I'm also a bit confused by your question/statement. Are you trying to determine the capacity of the pier? Is your lateral load high?

 

[mcutchi]

I'm as confused as Ron. Your pile is short & stiff. For whatever reason you need the point of fixity (do you mean center of rotation ?) try the brinch-hanssen method - works well for short piles.