Need some Physics help here!! Students/Teachers please help!!

MikeT

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Jan 17, 2001
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Ok, I am having a little issue here trying to figure out some Physics and I haven't taken a Physics course in over twenty years. Don't be too hard on me about incorrect terminology as I'm sure I am wrong about a few things.

Here is the problem;

Backround: I have a garbage facility that has a concrete wall and they want to make the wall taller with some steel posts and basically make a raised fence connected to the top of the concrete wall.

Problem; I have calculated that when a 2857 Kilograms horizontal load is pushing on the new extension (no speed or impact), the bolts will be at their maximum capacity. The front end loaders will frequently throw a bucket full of garbage at the wall and I have calculated that 907Kg (bucket capacity) of garbage being thrown at 2.23 m/s (estimated speed) has the Kinetic energy of 2,255 joules. K=1/2 m*v^2.

What I am having trouble with in my mind is coming up with a way to determine how much the wall can take because I don't have the velocity component to stick in the equation. I do have the mass that it can resist, 2857Kg but no speed. I want to be able to say that the wall can resist xxxxxx Joules and it is more than the 2,255 joules being thrown at it.

Can anyone of you smart guys shed some light on this? If you need more information, I will be waiting with bated breath for any responses.

Thanks!!
 
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RM_guy

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I haven’t taken physics for over 30 years but I still apply it almost every day. I just have to refresh my memory from time to time. The velocity of the mass that impacts the wall will develop a G force that you multiply by the weight to get the actual force that the wall will see. You can then use that value to calculate the stresses. If you are at the limit without any velocity then it won’t be strong enough with any speed.

Calculating the kinetic energy is just part of it. Here a web site that explains it pretty well. http://www.ehow.com/how_7617983_calculate-force-impact.html
 

Papakeith

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Aug 31, 2000
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you lost me at "Here's the problem;"

look me up when you need help with chickens, cows, or bees
 

RM_guy

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Papakeith said:
you lost me at "Here's the problem;"

look me up when you need help with chickens, cows, or bees
How about corn? You grow some pretty damn good corn. :nod:
 

MikeT

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Jan 17, 2001
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RM_guy said:
If you are at the limit without any velocity then it won’t be strong enough with any speed.
I don't think that the garbage being thrown at it will bring it to that limit, I just want to calculate how close it is getting to that limit. I will go and look at the website you posted.
 

MikeT

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Jan 17, 2001
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That article gets me the impact force and it looks like I'm correct on that, I just need to get the resisting force into joules or newtons.....
 
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