Re: Determining balsa stiffness

From: markdrela <drela_at_mit.edu>
Date: Sat, 14 Jan 2006 03:00:25 -0000

--- In Indoor_Construction_at_yahoogroups.com, Kurt Krempetz
<krempetz_at_y...> wrote:
>
> I believe the method they are using to determine
> stiffness or actually modulus of elasticity of the
> balsa wood is to find out at what load buckling
> occurs.

Ah, that's another way to do it.

One possible problem with this buckling-load method is that the test
piece must be very straight, and the load at each end must the applied
at the center of the beam. Any built-in beam curvature or off-center
end load will cause premature buckling and an underpredicted modulus.
 I don't know how much error this might cause in practice.

The 3-point bending test that I posted does not require the balsa
piece to be perfectly straight. It might be interesting to compare
the results of the two methods.
Received on Fri Jan 13 2006 - 19:00:50 CET