Size of a pier
Size of a pier
(OP)
A 600mm (2ft) long reinforced concrete pier is required to carry 2150kN (482kips) axial load applied on 250x250x50(10"x10"x2") plate. Your concrete f'c=35MPa(5000psi). What is the pier size and required rebars? This is not a school problem. I will provide more info after getting some feedback. Thanks






RE: Size of a pier
RE: Size of a pier
50mm is a very thick baseplate.
I would have a 450mm or 600mm diameter pier with 1% reinforcement.
RE: Size of a pier
In my neck of the woods, the geotech engineer would usually specify the minimum reinforcing required in the pier as a function of cross sectional area (usually 1 to 2 percent).
If you have to resist axial tension, then you must ensure you have sufficient steel present (and developed) to do so. The mechanism is that the base plate transfers load to the pier, which in turn transfers the load to the longitudinal steel in the piers and, finally, the steel transfers this load through friction to the subgrade.
RE: Size of a pier
RE: Size of a pier
RE: Size of a pier
RE: Size of a pier
In summary:
Base plate in accordance with design guide 1 (including bearing stress check)
Pier soil interaction in accordance with geotechnical principles
Check pier for combined bending/axial force as a short circular column.
I would normally allow for a misalignment of up to 150mm in my calculations.