Support reactions, castigliano's second.

[kantti]

Homework Statement

Determine the support reactions for the given structure(see attachment) due to flexural deformations using castigliano's second theorem. Axial deformations are considered negilible.

Homework Equations

delta = dU / dP

The Attempt at a Solution

See attachment. I could use some advice on how to continue. Thanks.

 

[vishal007win]

in such questions u don't have to differentiate with respect to force...do it with respect to displacement...n then by using relations replace it with the support reactions..

 

[pongo38]

It would help if you didn't assume that the Right hand reaction was P/2. It is less than that because the encastre support at A attracts load to it, this being a statically indeterminate structure. Have you obtained all the reactions and checked external equilibrium before starting all those integrals?