Can road bumps excite frame eigen frequencies? During my last bike holiday I have happened to ride downwhill on roads which had transversal stripes to mark the approaching of a turn.



The stripes were made with road paint, and were slightly higher than the road plane, so that passing on them makes you feel the bump.

At the speed one can reach while on downhill the repeated "ta-ta-pum" is non comfortable, so I was induced to slow down.

However I was wondering: could it happen that, for some particular speed of the bike, the bump frequency resonates with the frame Eigen frequency leading to potential catastrophic frame failure?
A resonant frequency encountered on a road surface would be for the whole bike system, i.e. frame, wheels, rider etc. The rider is effectively attached to the frame via elements with spring, damping and active control properties (arms and legs). Bumps encountered at a specific frequency might buck the rider off.

Bicycle frames are pretty stiff so any undamped resonant frequencies they have would be relatively high. Certain not at 10 or so Hertz you may get from riding on regularly spaced road bumps.

You assume that all structures fail when excited at resonant frequencies. This is plainly not true, otherwise acoustic musical instruments would self destruct when played. There certainly are structures where resonances can contribute to damaging oscillations of course, but I don't think bicycle frames suffer from this.