Effective Footing Width?
Effective Footing Width?
(OP)
Hi all,
I am looking at some old pad footings from the 1970's. They are larger than required (3m x 3m), but only 150mm thick with a single layer of F81 mesh central (Imperial, 503mm2/m). Looking to spread a load in a smaller section of two such footings of about 30kN inside a shipping container. Not sure of what width of the footing I should assume to be effective as I am sure the footing will not transfer the load across the whole footing. (I assume the container edge creates a distributed line load)
My intent is to analyse as a plain concrete footing (Min. steel not achieved as per AS 3600) and assume a strip-style reaction under the container edges. My initial guess would be to using AS 3600 Cl 15.4.1 to take 50mm off the depth to give 100mm. Then taking shear plane at 45 degrees, a conservative effective width of 200mm for the strip.
Does anyone know a better way to analyse this situation? How wide could I take this 'strip' to be? My assumption would be to use a steel baseplate to increase the width if required?
Thanks in advance!
I am looking at some old pad footings from the 1970's. They are larger than required (3m x 3m), but only 150mm thick with a single layer of F81 mesh central (Imperial, 503mm2/m). Looking to spread a load in a smaller section of two such footings of about 30kN inside a shipping container. Not sure of what width of the footing I should assume to be effective as I am sure the footing will not transfer the load across the whole footing. (I assume the container edge creates a distributed line load)
My intent is to analyse as a plain concrete footing (Min. steel not achieved as per AS 3600) and assume a strip-style reaction under the container edges. My initial guess would be to using AS 3600 Cl 15.4.1 to take 50mm off the depth to give 100mm. Then taking shear plane at 45 degrees, a conservative effective width of 200mm for the strip.
Does anyone know a better way to analyse this situation? How wide could I take this 'strip' to be? My assumption would be to use a steel baseplate to increase the width if required?
Thanks in advance!






RE: Effective Footing Width?
I would analysis this like a slab using the industrial pavement guide for point loads.
http://www.nceng.com.au/
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