This is a curiosity of mine. Could a boat with a carbon fiber or fiberglass hull be made as an Icebreaker? If it's thick enough, I'm certain it could handle busting through Ice. Wood ships did it. But is it more a matter of weight? What really makes a ship good at plowing through ice?
Wood ships used metal cladding. I remember when Jacques Cousteau brought Calypso into the Great Lakes and encountered ice, the cladding was below the water line because they were in less-dense fresh water. The ice started cutting into the hull until they added some cladding.
Although GRP is a lot tougher than most Woods abraision resistance is still one of the main topics when talking about ice.
Ice damage can happen when thin and slice into the hull like a razor. Then you may just as well be pushing thru & over granite bed rock in the heavy ice. A composite hull will loose without iron protection. Now, if your asking just about the strength / stress of the hull less the abrasion concern, Compression & suspension, I don't know. However, that may be moot anyway; the weight of steel & iron is needed to bust ice. The advantages of composite materials elsewhere, would be a disadvantage for ice busting.
I believe most ice breaker do not "plow" thru the ice. Rather they are designed to ride up onto the ice and crack it with the sheer weight of the vessel.
So I'm definitely going to need a steel hull if I want to get to the atlantic, from the pacific, via the Arctic.
Just try a submarine and avoid the ice topic... No, seriously, first you come up with the idea that structurally strong, but extremely impact sensitive material could be suiteable for an ice breaker, then you come up with the idea of an arctic passage which isn´t fun even for the professinals... I guess you just ought to to learn a lot more before letting the shore get out of sight. There´s a lot of water out there and it´s not allways friendly...
It can be done with a wooden hull: https://en.wikipedia.org/wiki/St._Roch_(ship) The way I'd like to do it (if I won a mega-mega-lottery) would be a trip on this: https://en.wikipedia.org/wiki/50_Let_Pobedy
Well, a lot oft things are possible, Arwed Fuchs did a number oft expeditions in polar waters with an öd Haikutter , a wooden saiiing Bessel from the Baltic with only 15m LoD. But for someone who is less experienced, qualified and prepared you might need Shackleton aboard to geht away with that.
There are two questions being asked; the one about ice-classed in the title and if carbon or fiberglass could be made strong enough. To the first, I would guess that the classification agencies would not consider the material appropriate. Bear in mind that carbon fiber and glass fiber are encapsulated in a plastic. As for the strength of the materials being sufficient to break through ice, the answer is yes, but only up to the point where the ice is weaker than the plastic hull. The same applies to steel and black iron. The Titanic was made of one of those materials, for example. And, Beau is correct in post #5.
The most awe inspiring ice breakers are the nuclear powered Russian ice breakers. Whatch some YouTube video on the subject and you will be amazed at the speed/force at which they traverse ice, hard to imagine without being there.
Carbon fiber is very strong and has a very strong weight to strength ratio, but it's impact resistance is lower than other materials and even fiberglass I believe.
Ironwood, a name that includes many woods, was once used for cladding wooden hulls for ice protection. It was still used after iron and steel was available, and still in use in the 20th century.
Of course it´s possyible to build a Carbon Laminate ice class vessel, you just have to clad about 2 ft. above and below the waterline with steel. one Inch thick should be completely sufficient. Well, considering that you´ll have a minor weight Penalty with that ice cladding and the structures to support it - compared to an all steel hull!