Foundation Design for Electricity Pylon
Foundation Design for Electricity Pylon
(OP)
A 5m x 5m x 5m concrete foundation has to be designed to bear the load of a typical electricity pylon.
What forms of and how much steel reinforcement bars have to be used?
Do bars have to cross through the whole cube or do they just have to form a cage???
What forms of and how much steel reinforcement bars have to be used?
Do bars have to cross through the whole cube or do they just have to form a cage???





RE: Foundation Design for Electricity Pylon
There are other material issues too with casting such a big lump of concrete!
RE: Foundation Design for Electricity Pylon
I had doubts aswell with the dimensions, but they are apparently required for the purpose of supporting the pylon.
RE: Foundation Design for Electricity Pylon
I would be concerned about 3 things in particular:
1. The amount of concrete used.
2. The bearing pressure on the soil(some soils would not be strong enough to support the self weight of the concrete).
3. The heat of hydration in the concrete will cause large differential temperatures throughout the concrete(google mass concrete ) also
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As per your original question, I believe this is one of the few situations where you would provide internal layers of reinforcement. Cant help you any more, sorry.
RE: Foundation Design for Electricity Pylon
http://www.cement.org/buildings/pdh_se_mass.pdf
RE: Foundation Design for Electricity Pylon
tower foundations (usually) use pyramid & chimney foundations, which reduces the load imposed by the foundation considerably.
Broadly this design uses the area of the base to carry the compressive load
and the depth of the foundation to cope with any uplift (outer legs on section towers, with significant deviations experience uplift - in the case of broken wires and wind - a lot of uplift)
when considering uplift the mass of a fustrum of soil extending from the edges of the base of the foundation out at an angle of 30 degrees up to fgl is added to the mass of the concrete. thus
base area - manages compression
depth - manages uplift.
a recent HDD crash resulted in the loss of all of my foundation spreadsheets etc. but i have copies at work....somewhere
to your original point about rebars - as far as i'm aware (and that aint far in the case of reinforcement) i believe that reinforcment (usually) takes the form of a cage.
alternatively augered foundations can be used, or even multiple augered foundations with a pile cap - these definately have cage reinforcement.
RE: Foundation Design for Electricity Pylon