Need formula for deflection

[aepeszel]

Hello

Does anyone know the formula for a cantilever beam under a sudden/shock/impact load? Machinery's Handbook, Roark & Young, and a couple of old school books did not have it.I have found the formula for stress in this case.

Thanks

Adam

 

[desertfox]

Hi aepeszel

Just thought I should point out that the stress I calculated
for the 'T' section only applies if the impact load hits as you originally described.
If the impact is at some oblique angle to the original then the 'T' section will have a different 'I' value and a different value of stress.
The calculation we have done uses the largest 'I' value you need to calculate stress using the lowest 'I' value.

regards desertfox

 

[kiwinjuneer]

Die-cast has very high strength compared to sand or investment cast. But it is also very brittle which is hardly conducive to impact loads and maybe some post-casting ANNEALING would be in order?

Aside from doing the dynamic stress calculations, I would also look very closely at the DISCONTINUITY stresses and ensure that there are no sharp corners or notches that could be a failure point.

My post doesn't doesn't answer your specific question but do consider a cantilevered vaulting pole. It would not even carry the STATIC weight of the vaulter but its design and flexibility is such that when in use it bends almost to horizontal and (hopefully) flicks the athlete over the bar.