News anchor: And when did you realize you had to evacuate? Survivor from the tiny town below: Once I saw the third geologist arrive I knew we were doomed.
"Stream of water flowing through sand" / "body of water held back by sand dam" has been consistently in my top five interests since I was five years old. I'm now 38.
Though the stream wasn’t even needed as you allready see the soaked wet body at the start… that’s why good dams are made up of diferent layers of material…
One of the interesting bits here is how subtle changes in the flow and slow-moving soil early on can catch the eye while skipping forward in 5 second intervals. There's a few movements in the early flow and slump that become a lot more obvious using the arrow keys to make the frames jump ahead.
The changes are so subtle that the human eye just doesnt catch them. I noticed the changes by skipping ahead and in live we just cannot see the shifting happening.
I ran this same experiment 60 years ago. I can hear my mother now, "Timothy! Stop messing around in the mud, get your tail in here and do your math homework!" Gawd, how I hated math! LOL!
I think the reason for the samples at the end was to measure mass of sand per volume of water. Multiply that by flow rate (volume per time) and they get mass per unit time lost from the dam. Plot that vs time. Then compare that with predictions from models; tweak the models to match the experimental data. If the match-up is qualitatively very different, then the model is too simplistic and missing an important feature.
@@koda0027yeah and the beginning of a human dying is the moment they’re born, that’s just semantics. He said the start of the *catastrophic* failure and you know it.
Saw a better example on another channel, an actual sand dam caused by a winter storm that blocked a river on the west coast of Africa. The river backed up until it over topped the dam, the result was the same but due to the far greater quantity of water the failure was awesome.
I wonder how mechanical stabilization using mesh (I used fiberglass mesh comonly used in construction) would effect this experiment and how would be most effective. My guess is about 90 degrees to the air face of the dam.
Was just about to comment about reinforced earth then I saw your comment, also you’d ideally want the mesh close to 45 degrees towards the water it would direct the force of the water downwards helping keep the dam strong
By 8:35 in the video you can see obvious erosion along the base of the dam from water leeching through the sand. Compare the bottom edge of dam at time 1:00 to 9:16, there can be no other explanation for this erosion of the bottom edge than from water leeching through the sand of the dam.
A thermal imaging camera might be useful in these experiments - warmer areas where the sand is dry, cooler where wet. A heat map would be the same as a moisture map, showing up the invisible seepage.
There's another video I've seen that this reminded me of. I encourage everyone to search for it. You should find it by searching "surfing standing wave California" It's a location in California where the beach forms a natural dam which allows a pond to form behind it every year. They purposely drain it each year and do so really similar to this. They dig a small trench towards the ocean which grows into a massive flow. The huge flow creates a lot of standing waves which surfers can ride sitting in one spot. It's really cool looking.
at what point did it become infeasible to recover? even as far at 40:30 i believe that maybe a handful of sand about halfway down the channel could buy you enough time to rebuild the downstream structure. do we have any data on the rate of bank erosion vs bed erosion? that is, how fast it cuts sideways as opposed to down, especially as the flow regime changes?
Do you think the guy leaning and moving against the side of the experiment affected it in any way? I imagine he caused it to flex at least a little bit as he put all his weight against the side several times.
I definitely think so, it sounded like it was told to not do so, but like a child he sneakily leans back up against it. I was waiting for catastrophic failure and him falling into the last bit of the reservoir.
Ground water can also be a supporting factor. I forgot the name of the city (Oops for all I know), it's location (Greece, maybe) and the time in which it was a city (the bronze age perhaps, possibly a little later), BUT I do remember that the city collapsed (literally) because the residents kept draining the ground water and it couldn't be replaced as fast as it was being drained until the weight on top of the dirt became too heavy and...the city fell down.
OMG, I’ve got a couple “take away’s” from this video. 1. The description said ( beach sand) Question what beach? 2. What were the dimensions ( aside from height) ? 3. What was the volume of the water? 4. What was the rate of replenishment of the water? 5. What was the purpose for taking samples during the final collapse, given that they were totally random? 6. How much did this “experiment “cost ? And finally how board was I to find this video and watch the whole thing? This was one hour that I’ll never get back ! P.S. DON’T BUILD A DAM OUT OF SAND!
I know a guy who had to deal with a dam failure like this in Loas. What started as a line ended up cutting thorugh a 50m high dam like a vertical knife.
What’s the point of the water samples toward the end? If I had to guess it’d be to see which particulates it was able to draw? Maybe each particulate had a different density so by analyzing the colors found in the samples timeline, you can determine what the flow rates were how much draft was created? Or am I completely wrong lol,
Yeah its already saturated that's why the bottom edge looks weird they should have put a sheet of plastic on the back side to prevent water from absorbing into the sand to make more realistic experiments
Actually, this why earthen dams should always have a clay core / base, since clay is denser and less permeable. If they had just maintained the water level and not overtopped, it would have failed anyway in less than a day I suspect.
Some must have been the water flowing over the top and then absorbing immediately into the face, progressively further down and absorbed into the slop-face, but I think the majority was water shoved straight through the compacted sand, like a pool filter?
My company: working from home will improve work efficiency. Me after 30 minutes of work: Look, they built a tiny dam!! Better see what's that all about!
Us - Here for the ASMR of watching sand erode. Dude offscreen - Would be a shame if someone ruined the experience with an impact drill BRRRTTTTT BRRRRTTTTT
If the saturation of the sand by water reduces the friction to such an extent that the structural integrity of the dam fails, could this not be counteracted by freezing?
Yes. However, the expansion of water as it freezes would deform the dam. Freezing from the inside out would bulge out both dam faces, and freezing from the outside in would crack and then dislodge the frozen faces. In either case, you would end up with internal cracks/discontinuities as the ice melts, and your entire structure would be unstable. Also, freezing is extremely expensive.
If this simulated a Earth filled damn not made from concrete but from earth materials did it also have a clay core or was it just sand. If it didn't have a clay core why not if you're trying to actually simulate it to this scale.
If you want to see this done on a macro scale, look up beach river surfing. Basically, there's a few places where a lake forms near the beach. Someone comes with a shovel and cuts a line. Just a foot wide, from the lake to the beach. In just a few hours you end up with something 3-5 meters wide with enough of a current to actively surf on. And then, once the lake/pond is emptied to the point that it equalizes, the sand is rebuilt by the tides dragging sand back in. It's pretty crazy.
At first this was about as exciting as watching paint dry. But then again watching a beaver dam collapse after a little human intervention is more fun. The beaver dam appears better constructed.
“He’ll watch literally anything”
-the algorithm
Hahahaaa
And I watched the whole video. What has my life become?smh...lmao
And here we are.
Most important takeaway for engineering students: Do not specify compacted sand as your dam construction material.
I'm not an engineering student but I could make that much since of it. Maybe I should be one,
Mechanisms at play would be exactly the same with reinforced concrete
Not without a moisture barrier.
they do dykes in moraine and compacted tailings, covered with a membrane and rocks, they hold for a long time with little to no issues.
@@richarddaigle8777 they do what now?!?!? 😳😳😳
Only geologists would throw confetti when a dam is failing.
This is probably just to visualize the flow rate for measurement.
@@Dhime You seem to have misunderstood his joke
@@aSinisterKiid I concur, good joke
@@tommelfinger One might say, A *dam* good joke......
made me LoL - Thanks
News anchor: And when did you realize you had to evacuate?
Survivor from the tiny town below: Once I saw the third geologist arrive I knew we were doomed.
"Stream of water flowing through sand" / "body of water held back by sand dam" has been consistently in my top five interests since I was five years old.
I'm now 38.
Though the stream wasn’t even needed as you allready see the soaked wet body at the start… that’s why good dams are made up of diferent layers of material…
I used to do this in the street guttter in front of my neighbor's house.
My mother used to call it “puddling” I prefer to call it empirical studies in fluid dynamics.
UA-cam algorithm clearly knows you better than you know yourself!
Ohhhh good for you!
"WHAT'S YOUR FLOW RATE, DAVE?"
"Uh, I'll have to consult my urologist"
"3 liters a minute."
"Dave, you better go see a doctor."
@@gravelydon7072 You'd need 5 people to match that flow rate (average human goes #1 at about 0.6L/min)
I'm not a geologist. Why did I watch this entire thing? The anticipation was killing me the entire time.
Are you familiar with ASMR ? I think this qualifies as a new type.
One of the interesting bits here is how subtle changes in the flow and slow-moving soil early on can catch the eye while skipping forward in 5 second intervals. There's a few movements in the early flow and slump that become a lot more obvious using the arrow keys to make the frames jump ahead.
The changes are so subtle that the human eye just doesnt catch them. I noticed the changes by skipping ahead and in live we just cannot see the shifting happening.
The entire video should have been presented in 10 second increments at the very beginning,if not 20 or 30 seconds until the movement became apparent.
I ran this same experiment 60 years ago. I can hear my mother now, "Timothy! Stop messing around in the mud, get your tail in here and do your math homework!" Gawd, how I hated math! LOL!
My killer was English class
I hated writing with a passion, but loved numbers
Too bad, you could have reconciled the two in geology/civil engineering and study/make/prevent this situation as a job ^^`
You know you are getting old when boring things become super interesting.
Thanks for sharing.
or young.
@@pauldwalker hey folks! We have a Benjamin Button here!
Or smarter
I think the reason for the samples at the end was to measure mass of sand per volume of water. Multiply that by flow rate (volume per time) and they get mass per unit time lost from the dam. Plot that vs time. Then compare that with predictions from models; tweak the models to match the experimental data. If the match-up is qualitatively very different, then the model is too simplistic and missing an important feature.
I don't think they were using certified standard average sand. It costs multiple thousands.
@@brunos6599 You watched that video too? NICE!
Dude none cares
I can't imagine the samples are very accurate as many of them were taken right at the moment of a collapse thus skewing the ratio of sediment to water
@@lyfewithpiglet582 Wrong
I have no idea how you watch this and NOT poke it! mad patience.
The absolute genius of the setup. Specifically the weights and shapes of the particulate and top cover for sampling.
This was the longest cliffhanger but when it goes it fucking GOES, bro!
A lot of small towns have learned that the hard way.
buddy with the confetti blaster gets REAL trigger happy the longer this video goes 🤣🤣🤣🤣
for compacted sand use 2 blocks, for more compacted use 64 blocks.
Minecraft 😂
A small boy's perfect day at the beach!
A grown up small boy asks "is the volume of water flowing increasing as an exponential?"🙂
Obviously not
40:00 Deep scoring
51:50 Start of catastrophic failure
The deep scoring part I agree with, but the start of the failure was at the beginning of the video when they broke the surface tension of the dam
@@koda0027yeah and the beginning of a human dying is the moment they’re born, that’s just semantics. He said the start of the *catastrophic* failure and you know it.
@@michaeldebidart Semantics are the whole point of experimenting and study. Without nuance, there would be no point.
Its cool that you can see the base slip out when you skip ahead a few seconds at a time.
Saw a better example on another channel, an actual sand dam caused by a winter storm that blocked a river on the west coast of Africa. The river backed up until it over topped the dam, the result was the same but due to the far greater quantity of water the failure was awesome.
link?
@@geronimo5537 maybe this one. ua-cam.com/video/psi62O-NHRQ/v-deo.htmlsi=hRlklucPBkvNmK7n
Part 1 ua-cam.com/video/psi62O-NHRQ/v-deo.html
Part 2: ua-cam.com/video/WdrNAQeGLNM/v-deo.html&ab_channel=WayneEaston
Geologists are so dam** funny.
Dude eagerly getting a juicy sample at the gush of a big collapse 😂
I wonder how mechanical stabilization using mesh (I used fiberglass mesh comonly used in construction) would effect this experiment and how would be most effective.
My guess is about 90 degrees to the air face of the dam.
Was just about to comment about reinforced earth then I saw your comment, also you’d ideally want the mesh close to 45 degrees towards the water it would direct the force of the water downwards helping keep the dam strong
The guy with the air gun must be paid by a hearing aid company! Wow that's LOUD!
Seen the same thing when some surfers dug a small channel from a river to the ocean. Didn't cost anything.
No idea what I'm watching, but I love it. Very peaceful video please do more! I love the rain
I *_LOVED_* doing this as a kid! It was my favourite hobby by far.
Why was this recommended to me? Why did I watch it?!?
Girlfriend: He’s probably watching porn on that computer
Me: I wonder what’s the hydraulic effect on defects in earthen dams.
Love the sound of pacing back and forth!!
By 8:35 in the video you can see obvious erosion along the base of the dam from water leeching through the sand. Compare the bottom edge of dam at time 1:00 to 9:16, there can be no other explanation for this erosion of the bottom edge than from water leeching through the sand of the dam.
Now I know I'm high af 🤣 I just watched an hour long video of a sand damns degenerative process 🤦♂️
I sat there watching the dam video and waiting for the dam breach. It was dam boring. 😂
2013 and the USGS is still workingwith video tapes. Let that sink in.
man id love to smoke a good one and spend the day hanging with these guys being fascinated by where the water decides to run
this is the work of every little boy that tried to dam the rain water in the gutter and then brake the dam🤣
Tapping forward so fast it looked like stop animation 🤣 loved it!😊
I used to do similar stuff as a kid. Go make a mud dam, turn on the hose, try to hold back the water. Fun times.
Holy shit. Now i want to see one without the line made in the beginning and see how long it holds
It would hold a bit longer, but not by much. The initial scoring is only made to control the point of failure.
@@Celebmacil I think it would have held for at least twice as long. But again this is the first super scientific model dam test that I've watched.
Superb! Never got to do this size experiment in my geol degrees.
A thermal imaging camera might be useful in these experiments - warmer areas where the sand is dry, cooler where wet.
A heat map would be the same as a moisture map, showing up the invisible seepage.
Don't know why I watched this. It was very interesting though. Thank you!
There's another video I've seen that this reminded me of. I encourage everyone to search for it. You should find it by searching "surfing standing wave California"
It's a location in California where the beach forms a natural dam which allows a pond to form behind it every year. They purposely drain it each year and do so really similar to this. They dig a small trench towards the ocean which grows into a massive flow.
The huge flow creates a lot of standing waves which surfers can ride sitting in one spot. It's really cool looking.
Here's a link actually
ua-cam.com/video/eDmoXkF-g9I/v-deo.html
Like watching paint dry for the first half hour, then it gets interesting. Water in action has to be seen to be believed.
I would have liked to see upstream and downstream results after the experiment.
What are they testing? Any hypothesis? How much water a certain amount of dirt can contain before it gives or erodes?
at what point did it become infeasible to recover? even as far at 40:30 i believe that maybe a handful of sand about halfway down the channel could buy you enough time to rebuild the downstream structure.
do we have any data on the rate of bank erosion vs bed erosion? that is, how fast it cuts sideways as opposed to down, especially as the flow regime changes?
The part you're looking for - 37:50
Do you think the guy leaning and moving against the side of the experiment affected it in any way? I imagine he caused it to flex at least a little bit as he put all his weight against the side several times.
I definitely think so, it sounded like it was told to not do so, but like a child he sneakily leans back up against it. I was waiting for catastrophic failure and him falling into the last bit of the reservoir.
Ground water can also be a supporting factor. I forgot the name of the city (Oops for all I know), it's location (Greece, maybe) and the time in which it was a city (the bronze age perhaps, possibly a little later), BUT I do remember that the city collapsed (literally) because the residents kept draining the ground water and it couldn't be replaced as fast as it was being drained until the weight on top of the dirt became too heavy and...the city fell down.
Middle part of Florida during the dry season. Sink holes develop and sometimes eat houses.
Damn them damn dams ,damnit !
Post 10 would be having nocturnal emissions from this video.
That boy would be thrilled to get a rake for his birthday
This just shows you can learn from being patient.
Wonder how many science teachers in high school refused to play this video because of the fart sounds 😂
OMG, I’ve got a couple “take away’s” from this video. 1. The description said ( beach sand) Question what beach? 2. What were the dimensions ( aside from height) ? 3. What was the volume of the water? 4. What was the rate of replenishment of the water? 5. What was the purpose for taking samples during the final collapse, given that they were totally random? 6. How much did this “experiment “cost ? And finally how board was I to find this video and watch the whole thing? This was one hour that I’ll never get back ! P.S. DON’T BUILD A DAM OUT OF SAND!
Not as bord as I am, I'm going to search for more to see how it compares to others ..
This was so cool
I know a guy who had to deal with a dam failure like this in Loas. What started as a line ended up cutting thorugh a 50m high dam like a vertical knife.
Great video, only thing i would recommend is to get your drinks from behind the dam in the future.
What’s the point of the water samples toward the end?
If I had to guess it’d be to see which particulates it was able to draw? Maybe each particulate had a different density so by analyzing the colors found in the samples timeline, you can determine what the flow rates were how much draft was created? Or am I completely wrong lol,
probably to tell the distribution of particle size and how much suspended particulate the water was able to carry.
What are all the collections used for toward the end of the video?
Would love to have seen another view focused on the end of that cut sooner in the test
What would be the effect of the earthen damn was planted? Would it slow or stop the erosion?
Have to ask, what happened in the first hour and a half? I love the experiment, and would love to see them done with various types of soil.
Did they ever determine why the toe slumped? Was there penetration through the lower layers?
The sand does look much wetter at the toe and appears to get drier as you move up the back face of the dam.
Yeah its already saturated that's why the bottom edge looks weird they should have put a sheet of plastic on the back side to prevent water from absorbing into the sand to make more realistic experiments
Actually, this why earthen dams should always have a clay core / base, since clay is denser and less permeable. If they had just maintained the water level and not overtopped, it would have failed anyway in less than a day I suspect.
Some must have been the water flowing over the top and then absorbing immediately into the face, progressively further down and absorbed into the slop-face, but I think the majority was water shoved straight through the compacted sand, like a pool filter?
Drainage inside the core to control erosion from seepage is a feature of some earth core dams
"Oh wow this should be cool.... oh crap.. 54 minutes?"
(54 minutes later)
"Yup, that was okay, I guess."
My company: working from home will improve work efficiency.
Me after 30 minutes of work: Look, they built a tiny dam!! Better see what's that all about!
Why does she take samples of the water? During full breach? Is it for the sand content?
Muy buena experiencia.
I did the same thing in my grandma's driveway one summer when I was a kid. She was not too stoked about it 😅
This video should have been played for those that signed off on the building permits of those houses built on a sand bluff
What are they doing with the impact wrench and can they do it somewhere else?
Why are water samples taken mid critical flow? To count debris particulates? Dirt?
What is the white wire that emerges from the left side of the carved-out area, around 51:47?
What are they collecting in the cups
“Boy, put your finger there and stay like that.” How The Netherlands were saved time and time again according to folklore.😊
What are they collecting at the end? Are they measuring the levels of confetti in each cup ?
Ah..so cute watching them play with tools
Genuine question: What was the air gun device being used? It didn't look like it was doing anything, but I'm assuming it was a part of the experiment?
It was blowing the little white particles onto the surface to show up the water flow.
Us - Here for the ASMR of watching sand erode.
Dude offscreen - Would be a shame if someone ruined the experience with an impact drill BRRRTTTTT BRRRRTTTTT
What the hell was a lm the sharp noises screeching and clicking towards the end??
So what are you sampling there as the dam fails?
I notice one strand of something holding a while section more stable !
If you're ever going to build an earthen dam, plant lots of trees and bushes on top, the roots help.
If the saturation of the sand by water reduces the friction to such an extent that the structural integrity of the dam fails, could this not be counteracted by freezing?
Yes. However, the expansion of water as it freezes would deform the dam. Freezing from the inside out would bulge out both dam faces, and freezing from the outside in would crack and then dislodge the frozen faces. In either case, you would end up with internal cracks/discontinuities as the ice melts, and your entire structure would be unstable. Also, freezing is extremely expensive.
Were the cups at the end used to find the flow rate of the sand?
Nah they were celebration mudshakes for the team
This was more fun to watch than soccer.
Scary, that they even developed a tool to hold the testbottles
Yes the absolute horror of researchers using tools…
A stick with a hole 😱
drink every time somebody says "steps". drink twice when dude says "downcut".
I'll watch anything to help me sleep at this point
What did the USGS learn from this experiment? What was the hypothesis being tested?
My biggest regret is not staying in school to become a geologist.
Earth dams are bulrush with a compacted clay core. Material above that, acts as a shield and ballast to keep the clay compacted.
I've got a lot of stuff to do.... So yes I'll watch a 50 minute video of a miniature dam failing!
If this simulated a Earth filled damn not made from concrete but from earth materials did it also have a clay core or was it just sand. If it didn't have a clay core why not if you're trying to actually simulate it to this scale.
Really shows what moving water can do.
If you want to see this done on a macro scale, look up beach river surfing. Basically, there's a few places where a lake forms near the beach. Someone comes with a shovel and cuts a line. Just a foot wide, from the lake to the beach. In just a few hours you end up with something 3-5 meters wide with enough of a current to actively surf on. And then, once the lake/pond is emptied to the point that it equalizes, the sand is rebuilt by the tides dragging sand back in. It's pretty crazy.
Here's an example here: ua-cam.com/video/eDmoXkF-g9I/v-deo.html
The best "plop" sound in the video is at 51:23 for anyone wondering
What happened to clock??
From 1.59.59 jump to 2.18.
What are the cups catching the sand for at the end?
Celebratory mudshakes for the team
I did this shit as a kid, and now you're telling me that I could've gone to school for this?!
Unconfined non cohesive soil..what did this prove again?
so hipnotic can loking wideo like this ol day
At first this was about as exciting as watching paint dry. But then again watching a beaver dam collapse after a little human intervention is more fun. The beaver dam appears better constructed.
Very interesting. What about underground breach