Arm stress equations

Hi folks. I'm looking at building a very large kayak type trimaran that is like a holopuni, but with adjustable arms and built for extreme strength for large waves like holopunis. Does anyone have resources on the equations of strength required for the arms for the load? I'd like a large trampoline area and am looking to make a very large kayak trimaran. Perhaps 24-30 for the main hull but in a wide kayak fashion. I wish to bring the pontoons down flat for when I'm not sailing to have lots of trampoline space. I don't mind having insanely large arms to ensure it's strength but would like to know a round about of stress that is from wider pontoon arrays.

 

Read professional boatbuilder magazine #182. That explains the basic principles. However, you are asking for a complete structural analysis and design. Most likely it is going to cost you. It will probably be wise to pay a NA or engineer to revise your drawings and provide a complete design.

 

Thanks for this link. I'm fairly studied on using solidworks and Matlab and will run Sims on Matlab after I complete the first design in solidworks.

 

The main focus of the build is to have a light touring triyak, that has ample trampoline space to put a 10x12 type camping cabin tent or half domestic tent to be erected on either or both sides of the trampoline. I also want it to be able to get in and out of surf swell around 6 to 10 foot. I realize a wide array will likely cause speed loss, but I am not too concerned with maximum speed, just want a super sturdy, large trampoline areas for coast and island touring and camping, and to put an e bike on the back, with about 4 to 5 people. Any suggestions for tall skinny hulls or similar builds I would love to see. Haven't found anything like it other than the holopunis. Which I don't believe the holopuni design is ideal for surf. Any suggestions at all are welcome. If the designs become super weak, I may just double or 3:2 scale other existing kayak trimaran models but increase strength at the arms and adjustable bracketing.

 

I found this link as a good rough draft analysis. Trimaran crossbeam calculations https://www.boatdesign.net/threads/trimaran-crossbeam-calculations.38345/

 

Maybe you can post a sketch of what you are thinking about. There is no way four kayaks tied together will survive 10 foot surf. They will capsize and roll, probably drowning you.

 

I'm thinking a trimaran like a holopuni. About 30' center hull and 26' amas. They fill with water when waves close out on them but am thinking splash guard tenting structure. You certainly need to go straight into waves or straight away. They surf em for 1000s of years in the pacific. Big wonky canoe sailboats in 20foot waves.