Question

1. A steel tie rod on bridge be made withstand a pull of 3500lbs. find the

diameter of the rod assuming a factor of safety of 2.5 and ultimate stress of

5700psi.

( Ans d=1.398 in. )

Answer 1

$A=\frac{KP}{\sigma}$

$=\frac{2.5*3500}{5700}=\frac{175}{114}$

$A=\frac{\pi}{4}*D^2$

$\frac{175}{114}=\frac{\pi}{4}*D^2$

$D^2=\frac{175*4}{114*\pi}=1.9545$

D=1.398in.