Re: Pier questoin
General discussion of pier design takes me back to prior experiences. I have built a few piers over the years. The most stable is this in ap-ug: Len Album:
This should link
The pier shown is extremely stable. It is fabricated from 6mm steel plate, the base is 600x600 and it is approx 1.5m high. It is attached to a concrete mass pinned to underlying hard rock.
I have made a similar one with 400x0400 base 1.6M high which also works well. It is attached to a 2.8M high concrete column 400 x 400 which has substantial footings.
The worst pier I have made was a round tube welded to a steel plate base and sand filled - it was terrible!
When one adds gussets to the side of a steel tube then you approximate the effect of a tapered pier. The gusts should be as wide as you can make them within reason.
Here is a guested pier:
The white pier here is made of high density cast iron and is a repurposed machine part, very stable. The pier is attached to a concrete mass in loose rock.