Question

What is the value of ${\theta }_B$ for the beam shown in figure below?

• A. zero
• B. $\frac{15}{2EI}\left(anticlockwise\right)$
• C. $\frac{15}{EI}\left(anticlockwise\right)$
• D. $\frac{30}{EI}\left(clockwise\right)$

Answer 1

The correct option is B $\frac{15}{2EI}\left(anticlockwise\right)$



Rotational stiffness of joint B

$\frac{M}{\theta }=\sum K=K_{BA}+K_{BC}$

$\therefore \frac{10}{\theta }=\frac{8EI}{l}=\frac{8EI}{6}$

$\theta =\frac{10\times 6}{8EI}=\frac{15}{2EI}\left(anticlockwise\right)$