Force need to crush a Can laying horizontally?

Question

Just can't find a suitable formula to calculate the force needed to crush an empty Coke- Can at its mid- point when laying horizontally. Where practicle tested carried out and the weigt needed for a Can to crush is 6kg which approx. to 58.86N. However research more then two weeks and still can't find the formula (theretical value)... Thanks

Answer 1

This is hard, because crushing is neither tensile nor compressive failure, but much more complex. I tried googling "buckling model" and "crushing model" but (within a reasonable period of time) couldn't find any crushing-related equations. Your problem is like but not the same as buckling since it's due to a side load rather than an axial load. While buckling is unstable (once initiated with a given load, full failure is bound to follow), crushing is progressive. A given amount of crushing of a given structure has an associated amount of energy. And with the 6 kg figure I'd guess that you're doing more than just initiating a crush with just an initial dent; if so, I believe your definition of crushing, from which to infer a force, is arbitrary. Also, unless your can snaps into a dent like an old-fashioned oilcan, there is no single force value that is definable in your process. This sounds like the kind of nonlinear problem that would be approximated by a simulation (also difficult) rather than analysis. However, here's one reference that mentions an analytical textbook by Gordon. See problem 3. Good luck.