Sound to destruct/ break concrete

In summary: Oakland Bridge collapse. God Bless you.Yes, it was a terrible thing to deal with. I was one of the people that was in theOakland Bridge collapse trying to free people from a very unstable structure. Wow. Were you a rescuer, or one of the luckier victims?To return to the OP, I think there would be a huge problem of impedance mismatch between the air / concrete interface (the two media have very different densities). Most of the sound energy would be reflected. It could, however, work better underwater because the density of water is nearer that of concrete. Kidney stones are broken up using ultrasound pulses on this principle. Also, there
  • #1
Bounty Hunter
4
0
Would it be possible to break concrete into rubble with sound?


if so, How much energy would it take?



Forgive me if this is a stupid question, I am not a physics guy but am trying to learn.


Joe
 
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  • #2
Sound or pressure waves are the wrong sort to disrupt concrete.

The damaging ones are the shear waves a la earthquakes.
 
  • #3
Bounty Hunter said:
Would it be possible to break concrete into rubble with sound?


if so, How much energy would it take?



Forgive me if this is a stupid question, I am not a physics guy but am trying to learn.


Joe
Yes it might be possible using ultrasonic shock waves.
These are not concrete http://en.wikipedia.org/wiki/Lithotriptor though similar.
 
  • #4
My thought are if we can make sound crumble concrete we can use this device to rescue people in a a colapsed building. without heavy equipment.
 
  • #5
Bounty Hunter said:
My thought are if we can make sound crumble concrete we can use this device to rescue people in a a colapsed building. without heavy equipment.
You may have a few conceptul hurdles to overcome.

1] What would happen to the survivors when they are hit with a shock wave powerful enough to shatter concrete?
2] What would happen to the survivors when the concrete is shattered to rubble over their heads?
3] What would happen to the structure - already highly unstable and liable to collapse at any moment - if you start reducing parts of it to rubble?


The purpose of heavy machinery is that it can remove large pieces one-by-one with a minimum of disturbance - and thus danger to the survivors - to the existing unstable pile.
 
  • #6
DaveC426913 said:
You may have a few conceptul hurdles to overcome.

1] What would happen to the survivors when they are hit with a shock wave powerful enough to shatter concrete?
ok i'll admit we have some hurdles.

2] What would happen to the survivors when the concrete is shattered to rubble over their heads?

my thought, I was one of the people that was in the oakland bridge collapse trying to free people from a very unstable structure. but i noticed then we had to shore up the bridge on top of us, but we some of the tools were to big to get into the small areas. If i could have shored up the area around the victim and had a smaller unit that would blast the concrete off it would seem to be easier and faster ( in a perfect world )
3] What would happen to the structure - already highly unstable and liable to collapse at any moment - if you start reducing parts of it to rubble?

we would still have to shore it up around the traped people, maybe the rubble could be vacumed out with the large 8" hose.

just a thought

forgive the spelling errors



Joe c
 
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  • #7
You were one of the rescuers? God Bless you.
Must have been a terrible thing to deal with.
 
  • #8
Bounty Hunter said:
...I was one of the people that was in the oakland bridge collapse trying to free people from a very unstable structure...
Wow. Were you a rescuer, or one of the luckier victims?
 
  • #9
To return to the OP, I think there would be a huge problem of Impedance Mismatch between the air / concrete interface (the two media have very different densities). Most of the sound energy would be reflected. It could, however, work better underwater because the density of water is nearer that of concrete. Kidney stones are broken up using ultrasound pulses on this principle. Also, there is a Shrimp which stuns its prey this way (can't remember its name. though).
The Reverend Ian Paisley used to work along the same lines. Fairly successfully, too, on occasions.
 
  • #10
It was a long time ago, I was called into help shore up the lower bridge from falling further. It was sureal. after a few days the spell of rotting flesh was overwelming. I went 5 days without sleep on adrenline ( or the fear that i would be crushed )

anyway sometimes i still see clips of me on with Dan Rather, Peter Jennings, Ted Kopple and the other CNN. I don't know where all those old clips are kept but one of my kids was watching tv and said ..Dad is that you? Its weird how life puts you in places to test yourself.

So much for the rambling. Thanks for the answers.

Joe C
 

Related to Sound to destruct/ break concrete

1. How does sound cause concrete to break?

The energy from sound waves can cause vibrations in the concrete material. These vibrations can weaken the bonds between the particles of the concrete, leading to cracks and eventually breakage.

2. What frequency of sound is needed to break concrete?

The frequency needed to break concrete varies depending on the type and strength of the concrete. Generally, high-frequency sound waves (above 20,000 Hz) are more effective for breaking concrete than low-frequency waves.

3. Can any type of sound break concrete?

No, not all types of sound can break concrete. The sound waves need to have enough energy and the right frequency to cause the desired vibrations in the concrete material.

4. Is it safe to use sound to break concrete?

Yes, it is safe to use sound to break concrete as long as proper safety precautions are taken. This includes wearing protective gear and ensuring that the sound waves are directed towards the concrete and not towards people or other objects.

5. What are the advantages of using sound to break concrete?

Using sound to break concrete can be more precise and controlled compared to traditional methods, such as using explosives. It also produces less noise and minimizes damage to surrounding structures.

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