How to decide longitudinal & transverse BHD position for a Ship/Barge

Discussion in 'Boat Design' started by Farhad, Mar 31, 2018.

  1. Farhad
    Joined: Mar 2018
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    Location: Singapore

    Farhad New Member

    Dear Sir's
    I am a new member of this forum, currently assigned to do a scanting calculation for a box shaped barge given with principal dimensions and other data as follows: ( The assignment is just for my learning purpose)
    L (Scanting): 200 m
    Beam (mld): 36.0 m
    Depth (mld) : 11.9
    Draft (design): 7.9
    Draft (Scantling): 8.0
    beside these if the deck loading, Longitudinal & transverse spacing is known,
    How could I select the number & location of transverse & longitudinal BHD?
    How about location of aft and fwd collusion BHD?
  2. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    Your barge will probably need to comply with the rules of a classification society. See these rules that will clarify many things. On the other hand, the needs in ballast or other tanks, if you have them, will help you decide the number and position of some bulkheads.
  3. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Check what stability rules the vessel is designed to satisfy, and then run a damage stability analysis, using the IMO standards as guidance for minimum distance between WTBs as your first guide.

    Given in IMO/Class rules.
  4. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    damage stability analysis for a barge?. I don't think so. A study of floodable lengths would be more than enough.
  5. C2 Naval
    Joined: Apr 2018
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    Location: Madrid

    C2 Naval New Member

    Hi Farhad,

    As TANSL said in his first post, you should follow a specified Class Rules for a barge, mainly for its main dimensions and for Class Society purposes. As per this point, many of Class Society has different rules according the main particulars of the design (self propelled, ballast tanks, etc.), so you must define it before.

    As a general note and thanks to a past barge Projects (50m and 100m) a damage stability study was not required by the Class. Normally, you can find the necessary documents and drawings in the corresponding rules to apply.

    Do not hesitate to share your next steps!
  6. jehardiman
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    jehardiman Senior Member

    Actually, a damaged stability analysis is dependent on what the barge is used for; I know for a fact that a berthing barge and one transporting certain hazardous materials require them here in the US. See 33 and 46 CFR.

    Even if there is no subdivision requirement, there may be a cost/deadweight/scantling/strength tradeoff. Depending on your cargo requirements and framing choice you may be able to tradeoff shell thickness/frame spacing/bulkhead spacing against fabrication cost/weight.

  7. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    @jehardiman, if you say so, I'll have to believe you but, frankly, I have serious doubts. Perhaps for a very special type of load, with a very special type of barge, it is necessary to make a stability analysis after damage but I am not able to imagine what that special case could be. Nor am I able to imagine that "cost / deadweight / scantling / strength tradeoff". Complementary information would be very interesting (keep in mind that I do not have the USCG regulations).
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