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Homework Help: Strain Energy - Displacement

  1. Jan 10, 2010 #1
    Any one can help me solving this plzzzzz

    2vkm2r8.jpg
    http://i49.tinypic.com/2vkm2r8.jpg"

    My attempt
    At A-B
    There is No load so dM/dP= 0 and dU/dP= 0

    At B-C

    M = -px - wx.x/2
    dM/dP= -x
    dU/dP = Wx^4/8EI

    At C-D

    M = -Wb + Px
    dM/dP = x
    dM/dP = -Wbx^2/ 2EI

    When i include all vaues to compute total starin energy, (AB+BC+CD)
    it shows a value of 0+ 444.44-2222.22 = -1777.78

    Strain energy = 1/2 x(load.)x (deflection)
    = 1/2 x 2000 x deflection.

    When i equate both valuse, i get deflection value of 1.78m which looks like very big value for a beam of 260mm long
     
    Last edited by a moderator: Apr 24, 2017
  2. jcsd
  3. Jan 10, 2010 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    Hi pradi4u! :wink:

    Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
     
  4. Jan 10, 2010 #3
    HI,
    Thanks for the reply. Here is where i am stuck
    At A-B
    There is No load so dM/dP= 0 and dU/dP= 0

    At B-C

    M = -px - wx.x/2
    dM/dP= -x
    dU/dP = Wx^4/8EI

    At C-D

    M = -Wb + Px
    dM/dP = x
    dM/dP = -Wbx^2/ 2EI

    When i include all vaues to compute total starin energy, (AB+BC+CD)
    it shows a value of 0+ 444.44-2222.22 = -1777.78

    Strain energy = 1/2 x(load.)x (deflection)
    = 1/2 x 2000 x deflection.

    When i equate both valuse, i get deflection value of 1.78m which looks like very big value for a beam of 260mm long

    Kindly help me to complete it.
    Your help is highly appreciated
     
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