— Good Thinking
Ancient Egyptians likely used damp sand to help move pyramid-building blocks
The miniature sledge-testing rig used in the study
In Egypt's tomb of Djehutihotep, a wall painting depicts someone pouring water into the sand in front of one of the sledges that hauled the blocks used in the construction of the pyramids. According to new research, they had a good reason for doing so – by wetting the sand, as little as half as much pulling force would have been required to move those sledges.
The research was conducted by a team from the Foundation for Fundamental Research on Matter, and the University of Amsterdam. They built miniature versions of the laden sledges, which they pulled through trays filled with both dry and moistened sand.
When an optimum amount of water was added to dry sand, capillary action bonded the individual grains together, causing the material to become approximately twice as stiff as it had been. This stiffness kept the sand from piling up in front of the sledge, making it much easier to pull. Too much water, however, saturated the sand and caused it to lose that stiffness.
It's similar to the building of sand castles, in which damp sand holds together better than dry or sodden sand.
The painting from the tomb of Djehutihotep
While there currently aren't many people attempting to build giant pyramids, the researchers believe that their findings could nonetheless have some practical applications. In particular, the knowledge could be used "to optimize the transport and processing of granular material" such as asphalt, concrete or coal.
A paper on the research was recently published in the journal Physical Review Letters.
Source: FOM Foundation
About the Author
An experienced freelance writer, videographer and television producer, Ben's interest in all forms of innovation is particularly fanatical when it comes to human-powered transportation, film-making gear, environmentally-friendly technologies and anything that's designed to go underwater. He lives in Edmonton, Alberta, where he spends a lot of time going over the handlebars of his mountain bike, hanging out in off-leash parks, and wishing the Pacific Ocean wasn't so far away.
All articles by Ben Coxworth
Was the sand miniaturized in the test as well?
"the researchers believe that their findings could nonetheless have some practical applications"
Really? Have these researchers never been to the beach? I learned all of this the first time I went to the beach. It is easier to walk or run on wet sand. Likewise, it is easier to drive a vehicle on slightly wet sand without getting stuck. This seems to be common sense among people who get outdoors, as well as construction workers who work with sand. But I have bad news for them for their future research plans, I already know it is harder to transport wet sand- unless of course I am using enough water to render it fluid.
This is old news. I saw it on a PBS special about building the pyramids. I would rather see extensive research on using sand/clay soil as a cheap building material. Adobe blocks/rammed earth/compressed earthen blocks are inexpensive but no scientific formulas exist for the earth mix based on the specific project, e.g., a privacy wall would require less strength (less stabilizer?) than a load-bearing wall.
To Dom: ask and you shall receive. I found several rammed earth fence articles online.
Ok, however... how did they get the blocks onto the sleds?
Which company sold those sleds and are they still around?
yeah, whenever I need to move an eighty ton block of granite I make sure it's on a bed of nice damp sand...and then get some aliens to help push it up the 400' ramp
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