Strength/rigidity of glue-laminated timbers

I’ve been doing a little very amateur glue lamination as part of my boat project and I was interested (although not entirely surprised) to discover that my laminated curved sections feel considerably stiffer than I would expect a solid piece of the same timber with the same cross section to be. I assume this is because the whole thing is stressed against itself.

Two questions:

-Is this increase in rigidity a well-known phenomenon, or am I possibly imagining it?

-Does this actually add actual strength, or can a laminated beam be expected to fail under similar loads to a solid one?

On a much smaller scale, when I make laminated spars, leading edges or whatever for my model planes the result is significantly stronger than a similar single piece part. It´s also heavier though.

That’s presumably the weight of the glue? What are you using? I’ve been using polyurethane glue which is incredibly strong, but quite light - possibly lighter than the wood it’s joining.

Sometimes I use cianoacrilate (Super Glue), sometimes white glue, but for me cellulosic cement works best. Of course the extra weight comes from the bonding agent, but when you´re laminating two 1/32" per 1/16" strips of light (5 lb x cu ft or less) balsa wood there´s little you can do to avoid adding significant weight.

Forest Products laboratory was the place that developed laminated beams. The last time I was there, they showed us the laminated wood I beams they were working on. They are in heavy use in the USA now. The site has way more content, than when it first went on the web. I don’t know what you’ll find there. I’ve been there before, and it makes for a nice tour, if you’re in Madison. It’s across from the UW Hospitals. They exist to keep the USA supplied with wood products as the demand rises and the supply lessens. They have a fire room too. They have demos of tests sometimes for scheduled groups that are related to the group’s interest. I got to watch them crack a laminated beam as a Senior in high school. The beam was maybe 3 foot thick, so it was impressive. They have a burn room to, where they set up a room and test how fast material might burn during a house fire. The laminated I beams are the best example of the strength of bonded wood I can think of.

I see they have a link for nanotechnology being the future for the forest industries, so I have to give it a look.