Will Kakehashi-kun act as a bridge for the world?
Cylinder’s symmetry breaking?
(July 22, 2015) Dr.
Ario’s major research field is applied dynamics and structures analysis. He
says that structures built using various materials, such as bridges and
buildings, are strong but they have the demerit that they can suddenly collapse
if they begin to develop a wrinkle. “For example, a cylindrical can, even an
aluminium can, is very solid when subjected to a vertical force. I think many
people have noticed how hard it is to crush an empty can in that direction. But
if we twist it a little, pressing at one point, we can crush it with ease.
Plastic bottles are also unexpectedly sturdy. The wrinkle that may develop for
many different reasons, such as the structure’s own rigidity or compressing
power, can suddenly produce an interesting shape. Do you know why?” he asked
me. As soon as it was apparent that I did not know the answer, he rolled up two
empty coffee cans back to back in some A4 size paper, and compressed it with a
little bit of power. He said “Please remember what you see because I will
explain what happens later”. Wrinkles were left in the paper along the regular
folds.