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Mechanical
Properties |
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·
The
solutions have the form of "standing waves" and the n = 1 solution is that
of lowest energy. The modes for a circular rod have an Euler buckling force
given by : FC=
( n2 π2
E I / L2 ) = (n2
π2
E A2 / 4 L2),
n = 1, 2, 3 .... |
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·
Three
buckling modes for the rod in compression are illustrated. The n = 1 mode
becomes unstable at the lowest value of Fc, and so this is the
normal failure mode.
· The
structural efficiency of this rod can be evaluated from FC
and m = ρAL
for the n =1 mode:
FC
(1) = (π
E A2
/ 4 L2 ) = (E/ ρ
2){m2π/4L2}
· Select
material on the basis of ( E /ρ2
) |
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From:
Polakowski and Ripling, "Strength and Structure of Engineering Materials,"
Prentice Hall (1966) |
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