waves on pontoon structure

Discussion in 'Boat Design' started by Hisham, Oct 23, 2005.

  1. Hisham
    Joined: Oct 2005
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    Location: Egypt

    Hisham Marine engineer

    I am designing a pontoon, the left side hull and right side hull will be connected to gather at the stern with a transverse steel bars or truss
    I know that in mono hull ship, the critical waves stress is sagging and hogging
    So where can I fiend a good description of wave stress act on pontoon or catamaran
     
  2. KCook
    Joined: Jan 2003
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    Location: Arizona

    KCook Senior Member

    As a practical matter, on small (24 foot) recreational pontoons, the main trouble is twist. One side rises for a wave out of sync with the other side. Sorry, don't know of any studies quantifying this.

    Kelly Cook
     
  3. sharpii2
    Joined: May 2004
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    Location: Michigan, USA

    sharpii2 Senior Member

    I would make some kind of allowance for flexing. The port hull may be climbing up a wave whie th starbord hull may be coming down one. With steel connecting beams, I would use some kind of compressable bushing under the connecting beams. Otherwise, I would have to worry about metal fatigue at the connecting joints.

    Either that or I would make the structure so rigid that it would hardly flex at all. This could be done with a large, thick box beam in the form of a wing deck.

    In a matter like this, experience is everything.

    Bob
     
  4. ted655
    Joined: May 2003
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    Location: Butte La Rose, LA.

    ted655 Senior Member

    A truss will not flex. A better design would be a torhsion bar. Or a walking truss, hinged in the middle, but under a type of tension by some device (spring?) to return the truss to normal surface rigidity.
     
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