Resonant frequency and structural integrity

[digidoodles5y4]

If someone could help me with my project, I'd appriciate it. I'm testing if an object's resonant frequency is linked to it's structural integrity. For example, if an object has a resonant frequency close to the frequencies of the sounds it's exposed to in an average day, wether it would be weaker than the same type of object with a higher or lower frequency. I plan to use wine glasses and metal, just to cover a range of different objects. What type of metal should I use (copper, aluminum, ect...) and in what form ( cans, pipes, sheet metal...)? And should I use more than one type of metal (compairing same types of metal to eachother, of course). Also, if you have any other advice for my project, I'd be glad to hear it. Thanks!

[agm]

Hi digidoodles5y4,

Welcome to the forum!

This is not a full answer to your question, but a few quick ideas:

--You might start by identifying frequencies that are present (perhaps at loud volume) in various environments, and then investigating objects that have been designed for use in those environments. A few things that come to mind: sirens, chainsaws, structures containing the huge organs used in churches...

--In case you haven't heard of the Tacoma Narrows Bridge incident, I think it will be of interest for your introduction. :) (We don't think of wind as sound, but both arise from density fluctuations in air.)

http://en.wikipedia.org/wiki/Galloping_Gertie
http://www.youtube.com/watch?v=3mclp9QmCGs
http://www.youtube.com/watch?v=P0Fi1VcbpAI

Best wishes,
Amanda

[digidoodles5y4]

Thanks for the advice, Amanda!
I really appreciate it. Thanks also for the links.

[agm]

Glad it helped! Feel free to post more questions in this thread as you complete your project.

Amanda

[Craig_Bridge]

The configuration and processing of metals will significantly affect their ability to withstand vibration. Copper can be hardened or left soft. The same applies to aluminum. Metals are often alloyed with other metals to change their behaviors.

With soft drink cans and other food cans, the contents will significantly affect the resonant frequencies and will also alter their crush strength.

The structural integrity of joints in materials is often where vibrations have the biggest effect on the integrity of some structure. Things like welds, solder joints, glue joints, fasteners, etc. are often what breaks or works loose first.