Alternative to Welded Stringers... Maybe

The idea is to design a free-floating internal support grid/Stringers between the hull and deck. This would be on an aluminum plate boat under 20 feet lets say.

The deck would use U channel framing under the skin of it or something similar. It would then be bolted to a handful of supports welded to the hull. In a way that compresses the grid against the hull. The grid sandwiched between the hull and deck would have a slight tapper down on the edges. The bolts would be tightened so the deck slightly flexes down to match the tapper, creating a small, intentional preloaded bend. This preload ensures a constant downward pressure on the grid, maintaining firm contact with the hull.

Would this or something similar to these be possible or has it been done in production before?

 

I don’t think you can force the crown into the deck without deforming the hull.
Some drawings or sketches would be helpful here.

 

Idea is smart . Make it will may be more difficult . Any preloads need some check in .

 

I attached a few quick mockups. The transom would need to be welded into the main structure since pressure alone wouldn’t resist a pulling force. In S2, I tried to show how tapering the top of the lattice structure at the edges could help preload the floor’s U-channel and prevent oil canning. The deck could be fastened to the hull using supports welded into the strakes, which would spread the load across the hull plate and avoid creating an extra lip that could catch water. The entire lattice structure would likely need to be welded together for strength, though it might not be strictly necessary.

 

This grid would act as a composite, because it is not attached to the main supporting structure.
Also any movement of the supporting structure is likely to create 'gaps'....again, not supporting.

In theory, it sounds fine, but in theory, one must ask, where is the load path when the main structure is under an applied load. The load path is through the grid and its bolts, not the deck support as assumed.
The supporting structure for the grid, must be an order of magnitude stiffer to provide support and a load path.

 

I might be misunderstanding. Isn't the "green" grid the main supporting structure for the hull? I do see what what you are saying about the load path going through the bolts and the strakes instead of the grid directly. Assuming it is strong enough would that be bad?

 

Think of it this way:

If you have a strip/layer of say rubber, a strip of wood, and a strip of aluminium.
And for simplicity, they are all equal length.
If only the bottom layer, lets say this is the aluminium is fixed at the end, bolted.

If you apply a load at the centre of this composite beam, the rubber will not bend at the same rate as the wood nor the aluminium.
Additionally, there is no direct load path between each layer as they are free to move independently of each other. The only path is their contact by proximity, but the contact is not 'fixed'....it is merely owing to the axis of loading that one of the layers come in contact with the other. But each layer has its own stiffness, and EI. So in this case the rubber may deflect and contribute or it may not, depending up the relative EI and applied load.

Finally, the layer in brown is orthotropic, therefore any out of plane load this layer will not contribute to additional stiffness.