pilesmakesmiles
Structural
I'm working on a project where we have lots of sites which require additional 300mm dia. ducting installing (for gas extraction). The ducts are generally elevated 2.1m above ground on metal stands to allow people to walk below to access other parts of the site.
On other projects ('designed' by others), a 500x500x300mm concrete base has been used and so far seem to have performed adequately. The ones I have designed are significantly larger, up to 850x850mm square.
The governing criteria is overturning due to the wind load on the ductwork. Bearing pressure and sliding are fine.
The bases are generally constructed at ground level (i.e. not buried) so I'm reluctant to take any passive resistance from the soil. I have asked if the ducts can be laid at a lower level but this is not possible.
Is there anything I might be missing which could help me reduce the size of my footings?
On other projects ('designed' by others), a 500x500x300mm concrete base has been used and so far seem to have performed adequately. The ones I have designed are significantly larger, up to 850x850mm square.
The governing criteria is overturning due to the wind load on the ductwork. Bearing pressure and sliding are fine.
The bases are generally constructed at ground level (i.e. not buried) so I'm reluctant to take any passive resistance from the soil. I have asked if the ducts can be laid at a lower level but this is not possible.
Is there anything I might be missing which could help me reduce the size of my footings?