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Design\modeling advice for unorthodox structuretructure

  1. Jan 26, 2016 #1
    hello! first time poster here. i am looking for advice in the construction of a suspended triangle shaped platform, made priciply of a web of seatbelts under a layer of ripstop, all sown together. using trees or rocks to anchor the corners of the triangle. (this type of tent has been done on a smaller scale sucsessfully under the name "tenstile", using rathcets to tighten the line) is there any way to model the slack and potential stretch of the material? or even just to see at what weigh the web will start to sag. my thoughts are that with a six inch ratchet and 6 in seatbelt material line the structure will be taunt enough to hold three full adults. i have uploaded a pic for visual referance of the webb pattern, the triangle is 26 feet on each side.

    Attached Files:

  2. jcsd
  3. Jan 26, 2016 #2
    I think we'd need a little more info on a few things, like how much sag is acceptable (you'll always have some), and how much pull you can get on the 6" ratchet strap. How much sag you get in the middle of it will also depend on if you put a preload on the internal web segments, thus increasing the tension on them...

    I don't have the tools or know-how to analyze something like that, if the weight of the 3 people is 500 lbs, and you put them in the center, and let say you have a 5000 lb pull on the strap (I think that's well within the working range of a 4" truck tiedown strap), and draw the vector diagram, you'd get at least the minimum sag (perhaps not the maximum though).

    Do you have anchor points that are really capable of holding even close to what a 6" strap can pull?

    Someone more knowledgeable than me is going to have to take it from here

    Welcome to PF :)
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