Structural strength to weight

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deleted-28403
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Project Question: On the page http://www.sciencebuddies.org/science-f ... h010.shtml, what is the structure used for the balsa wood picture supporting 900 kg - is it an isotruss or something different? Where can I get more details about that and similar structures
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Structural strength to weight

Post by deleted-28403 »

On the page https://www.sciencebuddies.org/science- ... h010.shtml, It says 18g can hold 900 kg. What was the balsa wood structural form used - was it an isotruss or something else? Could you please provide complete details of that structure?

Also, where can I learn about the comparative advantages of various structures?
kgudger
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Re: Structural strength to weight

Post by kgudger »

Hello and welcome to the forum.

That structure was built as part of an Odyssey of the Mind contest. You can search for information about those contests to get more information. Along those lines, you can also check these sites: http://www.zimsweb.com/balsa/index.htm, http://www.google.com/url?sa=t&source=w ... vhqLkUS9eg, and http://www.balsabridge.com/

Hopefully someone who created the science buddies page you mentioned will chime in with more info. HTH.

Keith
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Re: Structural strength to weight

Post by deleted-71588 »

Just looking at the photograph of the crushed structure after the fact, it appears to be a captive column variation. Compression strength of any wood beam is extremely high. The typical failure mode for any light weight column is flexing. Captive column designs wrap the vertical column assembly with something that has a high tensile strength to prevent flexing outward and use a cross bracing design to pre-bow the beams slightly outward.
-Craig
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