Question

A propped cantilever beam ABC is fixed at A and rigidly propped at C and loaded as shown below. The reaction at C is kN.

• A. 0.74

Answer 1

The correct option is A 0.74

Deflection due to UDL at point C,
$y_1=\frac{w\times 4^4}{8EI}+\frac{w\times 4^3}{6EI}\times 2$
$=\frac{1\times 4^4}{8EI}+\frac{1\times 4^3\times 2}{6EI}$
$=\frac{160}{3EI}$
Upward deflection at C due to propped raction R,
$y_2=\frac{R\times 6^3}{3EI}=\frac{72R}{EI}$
As $y_1=y_2$
$\Rightarrow \frac{160}{3EI}=\frac{72R}{EI}$
$\Rightarrow R=0.74kN$