Transversal deck beam section modulus with a hole

Discussion in 'Boat Design' started by Lucya, Jul 19, 2018.

  1. Lucya
    Joined: May 2018
    Posts: 28
    Likes: 0, Points: 1
    Location: Croatia

    Lucya Junior Member

    Please,
    if anyone can help me with on how to calculate section modulus for a deck beam partially having a hole on it, and by using CAD "massprop" for calculation.
    So I have calculated section modulus where the girder does not have a hole, but my concern is the result when there is a lightening hole (Beam is 400x7 with a 175mm hole in center + FB 100x10).

    Apologies if I failed on choosing the thread section.

    Thank you.
     
  2. TANSL
    Joined: Sep 2011
    Posts: 5,616
    Likes: 166, Points: 73, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    You must create the outer perimeter and the inner perimeter, both, as regions. Then use the command "sutract" to deduce the inner contour of the exterior. Now calculate the properties of the resulting region.
    You must take into account that the application will give you the properties regarding the current axis of the system. To obtain the real values of your profile, you must move it so that the center of gravity of its area is at the origin of system coordinates.
     
    Lucya likes this.
  3. Lucya
    Joined: May 2018
    Posts: 28
    Likes: 0, Points: 1
    Location: Croatia

    Lucya Junior Member

    TANSL,

    thank you so much for helping me in such a fast and very much understandable way.
    I get these results:

    0001.JPG

    THANK YOU one again :):):):)

    BR
     

  4. TANSL
    Joined: Sep 2011
    Posts: 5,616
    Likes: 166, Points: 73, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    The result will not be correct because you must place the set with its neutral axis at the origin of coordinates.
     

    Attached Files:

Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.