Newtons Bit
Penultimate Amazing
- Joined
- Apr 12, 2007
- Messages
- 10,049
For my purposes, what I want is an expression for force as a function of compression that I'm confident is an overestimate of the column resistance. If it's generally agreed that 3% is not only an overestimate, but a gross overestimate, then I can plug it into the model and see if there is still no jolt; if there isn't, then Szamboti's argument is refuted. At the moment I'm assuming linear increase in force up to the average of yield and ultimate strain at somewhere a bit above 0.2%, then constant force at that value up to 3%, which I think makes my columns twice as strong as Szamboti. I need to check the numbers again, but a first look indicates that the increase in energy absorption doesn't actually affect the jolt significantly; hardly surprising in retrospect, since it's the peaks in the acceleration I'm looking at rather than the collapse time (which is very much affected by the energy absorption). Since I was using ultimate strength rather than yield strength, the jolt is actually less. I'll post some results when I've checked them, but it still looks like - for the structure I've defined - no jolt by the time the angle reaches half a degree.
Ryan, sorry for intruding into your thread with a rather off-topic discussion. Maybe I should start my own thread some time.
Dave
Yes, yes you should start your own thread
