3 ms·
I've got a tough one for you. Some guys from material science lab claimed that with massive wooden structures the strength doesn't scale when size goes up. But
by vlehto 11y ago
I've got a tough one for you. Some guys from material science lab claimed that with massive wooden structures the strength doesn't scale when size goes up. But they were unable to explain why. They just claimed that welded steel is somehow lot better for very large stuff. Have you heard about such? And why does it happen?
I'd imagine it would go other way around, as knots are typically the weak spots. And with bigger structure knots would be averaged out.
- alricb 11y agoOne possible problem is connections. You can make very large wood beams and columns, but then it becomes difficult to transfer the loads from one member to the other, because even a pretty big bolt will act on a fairly small area of wood.
- vlehto 11y agoIt's would be very good guess, but that problem occurs with small scale wood too.
- 3pt14159 11y agoOnly a guess: The strength between the grains of the steel has less variation than the strength between the grains of the wood. So as you increase the cross sectional area the likelihood of splitting goes up.
- vlehto 11y agoYeah, that is only easy reason I can imagine. You can cross the wood grain and turn it into "veneer". That would quickly average out natural wood grain out of it. But you can't cross the glue planes. Now if you scale that up, the likelihood of having faulty glue plane could go up. It still doesn't sound like static stress problem. More like fatigue causing delamination. I'm still bit suspicious because this would be too easy to explain.