Getting Buried In Concrete To Explain How It Works

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References:

Cement Chemistry and Sustainable Cementitious Materials

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Special thanks to our Patreon supporters:
Emil Abu Milad, Tj Steyn, meg noah, Bernard McGee, KeyWestr, Amadeo Bee, TTST, Balkrishna Heroor, John H. Austin, Jr., Eric Sexton, john kiehl, Anton Ragin, Benedikt Heinen, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Juan Benet, Ubiquity Ventures, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi.

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Written by Derek Muller
Edited by Trenton Oliver
Filmed by Raquel Nuno, Austin Bradley and Bryson
Animated by Ivy Tello & Mike Radjabov
Additional video/photos supplied by Getty Images & Pond5
Music from Epidemic Sound & Jonny Hyman: the Bill Wurtz inspired ‘Skyscrapers are made of sea shells’
Produced by Derek Muller, Petr Lebedev, & Emily Zhang

[Naegimaggu]

With all the abstract science, it's nice of Veritasium to focus on something concrete once in a while.

[Ajaykrishna_]

Please explain spaghettification while falling into a black hole

[colinmackay]

I'm a concrete truck driver and this video was not only very accurate but it also taught me quite a few things. Thank you

[SufyMusic]

At the burns outpatient ward at the hospital I work, a man said he got chemical burns from kneeling in cement. Good to see you have protection ❤

[thirdpedalnirvana]

Every kid on a roadtrip ever has wanted to slide down the forbidden slide at the back of the concrete truck. And Derek actually did it.

[ThemeParkBeast]

You have now cemented yourself as the best science/education channel. You don't just make stuff up you always have concrete evidence to back up your facts.

[Giggles]

Im so happy you finally mentioned "do not try at home" @19:22. There are many ignorant people out there that will. As you were being surrounded in concrete a kept having flash backs of my dad when i was a teen. He worked with concrete for many years. On one job concrete was setting as being poured due to mixer truck had broke while on way to deliver. So in the rush to get it poured so we could form it before full set, dad's boot was filled. He didnt have or take the time to remove boot and clean up. Kept working. By that evening we removed his boot got his foot and leg cleaned, as we cleaned, layers of skin fell off. And first few days after this while treating womb his skin was still rolling off. Took several weeks of ointments and bandaging and cleaning before it finally felt like the healing was happening. His foot and leg was scard for rest of his life. Wet Concrete is not something you play in!

[calebthompson]

I don't know if I have a medical issue or what but I'm literally addicted to this guys videos. I have a full time job with at least 20+ hours overtime and I've watched every single video he makes multiple times and even fall asleep to the videos I've already watched he reminds me of smarter everyday but these videos hold my attention more. Thank you so much for the videos.

[davecrupel]

"I did not expect it to feel this heavy."

You said it yourself, Derek.
It's _liquid rock._

[Awolraven]

As someone who has worked in the construction industry for a long time, but knowing nothing about concrete, the bottle of pop being mixed into the cement 100% sounds like something you'd tell a new guy to do lmao

[ElementofKindness]

Boy, can I tell you about the base PH of concrete eating skin. I've done many smaller concrete projects without issue, never wore gloves, and the worst effect is dry skin in the following days. But the largest job by far, was my own home foundation, and when pouring the footers, I was exposing myself to the wet concrete for very much longer. You know how if you're in a pool for a long time, your fingerprints and parts of the palm get all wrinkly. Well, that's saturated skin, and the base solution can dissolve that saturated skin quite easily, and that's what happened to me. No pain while it happened, and only because I noticed a little blood while screeding my forms, did I pause to see if a sharp stone may have cut me. I washed my hands, and to my horror, found all my finger/thumbprint areas and the palm at the base of each finger and thumb with holes eaten right through the skin. The next two weeks were very challenging and painful as they healed. I was surprised to see my fingerprints return though!
I don't do concrete work without gloves anymore. 😅

[Hoganoutdoors]

Retired architect here. Cement is the glue that binds aggregate together to make concrete. Concrete is thus a composite of Portland cement and aggregates. So saying cement and concrete are "mixed up" isn't just a bad pun. It further confuses the issue. Cement is often mistaken for concrete, and visa-versa is more accurate way to state the problem.

Cement = expensive chemical glue that cures through the process of hydration
Aggregate = cheap, inert structural filler
Admix = something that modifies the structural or aesthetic properties of the finished concrete, or the chemical properties of the Portland cement glue. Some admixes do both. It's all very complicated - trust me...

..and skyscrapers are not made of seashells. Their floors are. Their structures are made of mainly of steel and enclosed by glass hung from extruded aluminum sections, usually with lightweight, non-structural concrete floors poured into corrugated steel pans that span between secondary structural elements like wide-flange beams or light metal trusses. Most of concrete serves two main purposes - fire resistance and sound isolation. The only load bearing concrete will generally be low in the structure and used as footings, or sometimes as shear walls higher up. This is because thick load bearing structural concrete is ill suited for use in very high buildings due to it's mass.

Finally, infrastructure is not made from concrete alone. Bridges and roads and sidewalks are composite structures of concrete and steel reinforcement bars (rebar) engineered to exploit the compressive strength of concrete and the tensile strength of steel

[tescomealdeals]

This might actually be the first time I’ve seen a hydraulic press being used for its intended purpose lmao

[jeffreyokun]

I have first hand experience how concrete is caustic and dissolves skin cells. I had once a hellish concrete job in pouring rain, the pump truck was swimming in mud and the moulds were filling up with water, long story short, due to an almost biblical flooding that day (pump trucks have to empty or the concrete dries) we had no choice than fill up the molds even if we knew it was gonna be trouble. Due to the mud, the concrete started to burst through the groud from underneath the molds, and I had to get in there with a showel.. During the day I every now and then felt a tingling sensation on my hands while showeling, my gloves covered in slur.. Once the day was done and I removed the gloves, I saw that due to being soaking wet, concrete had turned into a soup, went inside my gloves and then marinade my hands in a caustic porridge through the whole day. As a result my fingers had turned black and had received 3rd degree burns. Turns out, unlike acids that cause a burning sensation, caustic attacks and numbs the nerves, so you hardly feel any pain, especially when frantically working to save the pour.

The fat and skin from my hands had basically dissolved away, and the chemical burns kept worsening due to the concrete causticity deeply penetrate my flesh. In the end I even had pockets to the bone in some places.. Recovery took an entire year with fixing the fingers, but today I have good mobility close to what it normally was. Be careful not to let concrete on your skin for long periods of time, it will eat through.

[ryanignites]

Seeing you run through the gravel resurfaced some serious nostalgia. I remember going to these big gravel yards as a kid and running all the way to the top to tell my dad which mound was the best to grab from. What a time

[vicmatthew]

Thank you for Derek Muller, Petr Lebedev, and Emily Zhang for creating the Bill Wurtz inspired bit, 'skyscrapers are made out of seashells'. It was hilarious.

[liamjackson]

As a concrete worker it’s nice seeing someone make a video about it. It’s dramatically under appreciated yet it’s in everyone’s daily lives. Thanks for the video

[aidenrf]

This really cemented my love for concrete demonstrations

[SnareGG]

that bill wurtz style "skyscrapers are made of seashells" part was great!

[kenesawthornley]

It was really fun watching this video, reminded me of the time I spent in a lab testing concrete cylinders out of highschool.

Something I didn't ever see mentioned in the video was that highest PSI does not always equal best concrete. for example, the landing strip at an airport wants a lower PSI tolerance because that in turn results in more flexible concrete, allowing it to endure the impact of the airplane. Then say for a building support column it wants higher PSI as it isn't expected to handle impacts, just bear a heavy load.

Take what I say with a grain of salt though, as this was several years ago, maybe it has changed since then, but if so I haven't heard about it.