Deflection at any point in fixed beam

AI Thread Summary
To find the deflection at any point in a fixed beam due to a couple acting at an intermediate point, Roark's Formulas for Stress and Strain can be referenced. The loading can be defined using singularity functions, which allows for the calculation of deflection by integrating the fourth derivative of deflection, EIy''''. This process involves determining the shear force and moment, followed by the deflection as a function of position along the beam. Integration constants are established based on boundary conditions, such as deflection being zero at the beam's ends. The discussion emphasizes the assumption of small deflections for accurate calculations.
sunil.hk1
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give formula or reference for finding deflection at any point in beam (fixed at both ends) due to couple acting intermediate in the beam? its urgent...
 
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sunil.hk1 said:
give formula or reference for finding deflection at any point in beam (fixed at both ends) due to couple acting intermediate in the beam? its urgent...

I'd start with Roark's Formulas for Stress and Strain.

CS
 
I think the easiest thing is to define the loading using singularity functions, set it equal to EIy'''' (where E = elastic mod, I = moment of inertia, y'''' = fourth derivative of deflection); then successively integrate to get the shear force, moment, and finally the deflection as a function of x (the position along the beam). and determining the integration constants from the boundary conditions (such as at x = 0 and x = l, y = 0).

example of the singularity functions
http://www.roymech.co.uk/Useful_Tables/Beams/Singularity.html

(this is assuming small deflections by the way)
 
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