Deflection Limits on Tall Sculpture
Deflection Limits on Tall Sculpture
(OP)
Hi,
I have a 11m high by 600mm wide boat sculpture standing on a foundation, effectively a cantilever. The spine structure is a CHS of sorts but I'm finding large deflections at the top of the boat (the tip). Anyone recommend a deflection limit for something like this? L/180...L/150? I know the boat structure itself which is 3mm thick polished stainless steel will give additional stiffness to the structural spine but its very hard to model.
Anyone know what that the deflection limit for highway light standards?
John.
I have a 11m high by 600mm wide boat sculpture standing on a foundation, effectively a cantilever. The spine structure is a CHS of sorts but I'm finding large deflections at the top of the boat (the tip). Anyone recommend a deflection limit for something like this? L/180...L/150? I know the boat structure itself which is 3mm thick polished stainless steel will give additional stiffness to the structural spine but its very hard to model.
Anyone know what that the deflection limit for highway light standards?
John.






RE: Deflection Limits on Tall Sculpture
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Deflection Limits on Tall Sculpture
8" carbon steel pipe (as opposed to tubing) should be readily available in heavier wall thicknesses if needed.
RE: Deflection Limits on Tall Sculpture
BA
RE: Deflection Limits on Tall Sculpture
My understanding of vibration due to vortex shedding will only happen if the structure shape is uniform along it's height. The boat shape I have changes cross section along it's height.
Any more takers on the allowable deflection limit for such a structure.
John.
RE: Deflection Limits on Tall Sculpture
1) Much more torsionally flexible.
2) Probably more torsionally loaded by wind.
In my head, I can see how it might twist and shed, twist and shed, twist and shed... hopefully not in resonance.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Deflection Limits on Tall Sculpture
RE: Deflection Limits on Tall Sculpture
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Deflection Limits on Tall Sculpture
RE: Deflection Limits on Tall Sculpture
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Deflection Limits on Tall Sculpture
There appears to be a flood elevation note on your drawing. Does this mean that the sculpture may be underwater at some point in it's life ... possibly subject to pressure from a flowing river?
RE: Deflection Limits on Tall Sculpture
Wow 1m deflection, now that's impressive. Yes the bottom 4m of the sculpture could be under water during a flood period but the sculpture location is well away from the main flow of the river, the flood water in question is overspill flood water from the river.
The sculpture wall thickness is 3mm stainless, could this distort under the water pressure at 4m depth?
Should I reinforce the infill concrete?
Should I increase the height of the spine internally to 3/4 the height of the actual structure?
As I am in a flood zone I guess I need to design the connection of the boat to the structural spine for the uplift forces due to buoyancy?
John.