Calculate Car Impact Force on Steel Structure | Help Needed from Belgium

AI Thread Summary
To calculate the impact of a small car on a metal structure, it's essential to understand that the force calculated (82.5 Newtons) is not dimensionally correct as it confuses force with momentum. The impact assessment involves complex factors beyond simple calculations, including the material properties of the structure and the nature of the collision. The steel tubes' dimensions and fastening method also influence how much impact the structure can withstand. Ultimately, real-world testing and experience provide more reliable insights than theoretical calculations alone. Understanding these complexities is crucial for accurate impact analysis.
Smirnoff103
Messages
1
Reaction score
1
Hello,

I need to calculate the impact that a car (small car) has on a metal structure.

What I know:
The mass of the car : 99 kg, the velocity of the car : max 3 km / h -> 0,833333 m / s
Thus the force of the car at 3 km / h is 82,5 Newton.

Now I need to know how much that metal structure can receive as impact.
The structure is made of steel tubes with keyclamps. The tubes have a diameter of 42,4 mm and they weights 2.57 kg / m.
The thing is that the structure is fasten in the ground with screws :p what doesn't make it easier to calculate I guess.

I know it's a long shot, but if somebody could help me out how I can try to find something out to give a result ?
The thing is I have learned all of these at high school but it's too long ago and can't remember :(

Thanks for your help.

Regards from Belgium
 
  • Like
Likes kaushikhm
Physics news on Phys.org
Smirnoff103 said:
The mass of the car : 99 kg, the velocity of the car : max 3 km / h -> 0,833333 m / s
Thus the force of the car at 3 km / h is 82,5 Newton.
Sorry, that result is not even dimensionally correct. The product of mass and velocity has units of kilogram meters per second. That is a unit of momentum. The Newton has units of kilogram meters per second squared. It is a unit of force.

However, you have another problem. Force, momentum, energy... None of them is a single magical number that equates to how much damage an impact will cause or how much a structure can absorb without permanent damage (though energy comes close). Collisions are complicated. Real world experience and experiment trumps high school physics calculations every time.
 
I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
Back
Top