How to Calculate Strain Energy for a Beam?

[pradi4u]

Any one can help me solving this pleasezzzz

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

 

[tiny-tim]

Hi pradi4u!

Show us what you've tried, and where you're stuck, and then we'll know how to help!

 

[pradi4u]

Hi pradi4u!

Show us what you've tried, and where you're stuck, and then we'll know how to help!

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