> Material properties don't vary when the shape changes.

Thank you, that is an answer I was looking for.

>As for how to
> relate the results from flat plates to curved plates and shells, you will
> need to read some books. I gave you a list.

> There have been failures listed on this board by people other than me. What's your definition of failure? Failure above and beyond the failure a solid fiberglass boat would experience in the same situation?

Catastrophic failure=ultimate failure. Not just simple elastic failure or a few broken fibers of glass. Failed so miserably that one wouldn't want to be paddling in the middle of any crossing after it happened.

> What you mean by the word catastrophic is beyond me. If I have to repair
> my boat before I can go out again, that is a failure. In many conditions
> it would be catastrophic.

That's catastrophic. If I get a big gouge and the boat still floats and I can still safely cross a 3-mile channel, it's not catastrophic.

> Using the construction methods of the authors you list neither I nor
> anyone I have personal knowledge of has been able to build a boat that is
> suitable for a two week trip.

Oh, really? :) Is that a challenge? I can do a 3-day trip with a normal amount of food and gear without any serious damage, and repeat the process multiple times before any repairs (other than scratches) are needed. I don't think adding 25 lbs. more food for an additional 11 days, and paddling continuously would cause the typical boat to spontaneously fail.

> Will more glass make a stronger boat? Depends on how you apply it. Of course.

Shawn