ROLLA - Sometimes, the best way to see how strong something is means shooting it with a cannon loaded up with stuff found in a coal mine.
While this may sound like a TV comedy bit, it’s part of serious research at the Missouri University of Science and Technology that could make coal mines safer for workers.
Large sections of coal mines are often sealed off with concrete barriers that are a few feet thick when they are no longer in use. Those seals lock in combustible gasses.
Kyle Perry, mining and explosives engineering professor at Missouri S&T, said the seals were designed to hold back increased air pressure and the force of a small explosion from the portion of the mine that is still active.Listen to St. Louis Public Radio's Jonathan Ahl's story on testing mine seals at Missouri S&T.
“Nobody has looked at what happens if that explosion picks something up, a concrete block, a wood timber,” Perry said. “If that explosion can pick that up and start hurtling it at these seals, are they going to become cracked, allowing air to pass through?”
Perry said even a tiny crack could let dangerous gasses through, and turn a minor mining accident into a huge explosion that could kill hundreds of workers.
Perry received a grant from the Alpha Foundation for the Improvement of Mine Safety and Health, and donations of seals from mining company Strata Worldwide to conduct the tests.
He and his students built an eight-foot cannon out of an industrial steel pipe so they could shoot objects at the concrete barriers to test them.
“Hard hats, tools, and pieces of machines, rebar … can they break a seal if there is a small explosion in a mine? There’s only one way to find out,” Perry said.
So far, what Perry and his students have fired from their homemade cannon has yet to do more than minor surface damage. But they are planning to try more items, with greater force and on a variety of seal designs.
They are collecting data that can be used to confirm the strength of the seals, and also show opportunities to improve designs to make them safer.
“It’s serious research, and ultimately it’s about the safety of mine workers,” Perry said. “But it’s also a lot of fun to shoot things out of a cannon. I love my job.”
Follow Jonathan on Twitter: @JonathanAhl
Send questions and comments about this story to
Copyright 2021 St. Louis Public Radio. To see more, visit St. Louis Public Radio. 9(MDA3OTgyNDI4MDEzMTM0MjQzMTZlNDI0Mg004))