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Old 16-11-2018, 10:09 PM
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ChrisM
Sandy Ridge Observatory

ChrisM is offline
 
Join Date: Mar 2008
Location: Gippsland, VIC
Posts: 763
Jason, my gut feel is that a pier 2 metres tall at 140 dia is a bit slender unless it is gusseted. I would use tapered gussets on the lower 2/3 of the pier. To keep the weight off the top half, I would avoid filling the pier with sand or concrete past the half-way mark, if at all. The 5 mm wall thickness should be okay. It's the pipe diameter that gives it most of its strength - not the wall thickness. Having too much mass up the pier lowers the vibration frequency, which is what you don't want.

Cheers, Chris
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