Concrete pier question

[carlmat]

I need to design a pier that holds a load of 26042 kN
I have gotten to the part where i have the dimensions which are 1300mm x 1300mm x 300mm for the plate. Now i need to design the pier, I am having trouble because i cannot figure out the amount of reinforcement that is needed and help would be greatly appreciated.

 

[carlmat]

wrong file in the first message

 

[JedClampett]

Are you sure your loads are right? They're pretty huge. And your question is about reinforcement (concrete design?), but your calculations are for the baseplate.
But using a 12 inch thick plate is a little out of the ordinary. If you need more bending capacity, you should add stiffeners to your flanges.
Blodgett, "Design of Welded Structures" gives some examples of stiffened base plates.

 

[dik]

Best to make the concrete pier as strong as possible in bearing... it will be in excess of 4' square... to minimise the size of the base plate. With 5000 psi conc (35MPa) you are looking at approx a 4'x4' baseplate. 26000 kN is a bunch of load...

Dik

 

[hokie66]

I'm confused. In one place, the OP says the "plate" is 300 thick, in another, he says 120. Then you guys start mixing the units. What gives? How high is this pier, anyway? Or is the 300 a concrete plinth under the 120 base plate?

 

[hokie66]

I am not sure which Code is being used, but you should be able to reduce the size of that plate substantially if it is based on the concrete bearing stress. Use the section of your Code for "Bearing Surfaces" or similar, which will allow a design bearing stress higher than fc', possibly 1.2fc' or another limit based on the ratio of the area of the concrete to the area of the steel. As well, it is often advantageous to use higher strength concrete for high bearing stress situations.