4/21/2024 0 Comments Does quicksand actually exist![]() ![]() Of course, NASA and Dr Lohse could have saved themselves a lot of trouble if they'd just watched The Princess Bride. Oh, Princess Bride, is there nothing you can't teach us? There was a chance the Neil Armstrong might have stepped off the Lander and disappeared into the dust. Even though the Lander made it down okay, nobody knew for sure if it would be okay for the astronauts to step onto it. The bottoms of the Lander legs were fitted with dish-like pads to help prevent this. The Apollo sites were particularly chosen for being hard and rocky to reduce the risk of the Lunar Lander just vanishing below the surface into a pit of dust. Previous lunar probes had confirmed a rocky, dusty surface on the Moon and there was concern about the packing fraction of the lunar dust. Now reducing the packing fraction from 60 to 40% doesn't seem like a big difference, but look what happened when they dropped a ping pong ball onto the sand.ĭuring the Apollo lunar missions, there was a very real fear of something like dry quicksand. When the air was turned off, the packing fraction of the sand had been reduced to 40%. In a recent experiment published in Nature, Dutch scientist Detlef Lohse and his mates built a box with a perforated base, filled it with fine-grain sand and passed air through it. As the sand has fallen back, the packing fraction has been reduced making for a much looser sand mixture. In dry quicksand, the airflow through the sand has flowed around each grain separating it from the others. Consider a ball-pit at a kids playground that's how sand is packed. Because of sand's rounded shape, it can't be packed tightly. Ordinarily sand has a packing fraction of around 60% - that's the ratio of sand to air in the mixture. The airflow moving through the sand causes it to become more loosely packed. Instead of water flowing through it, it has had air. But there's another kind which has long been a rumour, but has only recently been confirmed to exist: dry quicksand.ĭry quicksand is really scary. That's wet quicksand and that's the kind we've sort-of heard of. Now the quicksand in the video is relatively easy to spot because of the wet surface, but often the surface will be covered with leaves or even a dried layer of sand so it can be very hard to spot. He'd have a lot harder of a time getting out if he didn't. In the video, note that guy is smart enough to remove his shoes before stepping into it. Then exposure to the elements, dehydration, etc will kill them. There are regular reports of lone hikers getting stuck in a patch and not being able to get out. It's rarely more than chest-deep so you won't necessarily die from the quicksand itself, but it can be rather hard to get out and that's what really kills you. The flat surface that is the sole of your shoe will cause a vacuum to attempt to form under it when you lift it and then you're fighting against the suction of that vacuum. It won't suck you down per se, but there is suction all around you which makes it more difficult to extract yourself, especially if you're wearing shoes. But as soon as you step onto quicksand, it will just part beneath you and you'll sink down quickly. As it's mainly water, you can float in it without any problem. In real life, quicksand isn't very deep and it won't suck you under. “If you can imagine falling into a bowl of extremely watery oatmeal, it’s like that,” said Dimmick.In the films, as soon as you step into quicksand it sucks you in and you're dragged under to die. That’s the part the movies have all wrong.”Īnd what does it feel like to be immersed in the grainy stuff? “You can’t get sucked down into quicksand,” said Dimmick. But kicking and screaming in a panic can be dangerous. Those who do fall in can swim because humans can float in quicksand just as they float on water. “There’s probably more out there than some people realize,” Dimmick said.īut quicksand, generally, isn’t as dangerous as portrayed in movies, Dimmick said. Quicksand conditions do exist in Connecticut and across the United States.Īlthough most cases are caused by excavation and construction, said Charles Dimmick, a geology professor at Central Connecticut State University in New Britain, the right conditions do exist on pond floors or at the base of steep hills where there is wet sand. The disaster caused $1 billion in property damage. Water found its way under the foundation, creating quicksand and causing an 85 billion-gallon flood that wiped away two towns and killed 11 people. The most notable construction disaster caused by quicksand may be the Teton Dam flood of 1976. ![]()
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