Why Bridges Don't Sink

An overview of the different types of pile foundations and how they work.
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Bridge substructures are among the strongest engineered systems on the planet. And yet, bridge foundations are built in some of the least ideal places for heavy loading.
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[@PracticalEngineeringChannel]

⚡I have more than 20 videos about soil! kzbin.info/aero/PLTZM4MrZKfW-A419dqGZVtw6CAANqKR1f 🌌Get Nebula using my link for 40% off an annual subscription: go.nebula.tv/Practical-Engineering

[@WilliamPozo]

Years ago, i worked on a project using steel micro pile. which used reject oil pipe. Each 8' L x 8" D piece screwed into the next... was quite beautiful to see installed. Went to 140' and each pier had 16 of them!

[@gg-gn3re]

I'm interested in nebula but hesitant for over a year now. They now have a "buy it for life" thing which makes it even more tempting. Do they have a guarantee of 5 years of life? What if they cease to exist next year? I wish the 40% off annual sub gave you a 1 week trial option or something too. But I'd be interested in that lifetime purchase more than the subs

[@catdaddy3728]

Great info! Thanks! Hey, not on topic but remember the section of I95 in Phila, Pa that collapsed a year ago when a gas tanker crashed under it and burned and all the talk was how to fireproof these structures? Well, a year later it is completely rebuilt and guess what... no fire protection was installed as part of the design. Could have been a prototype for all to see... smh.

[@nekomata4830]

My favorite pile is the grounding rod

[@death_parade]

0:42 That is Mumbai. Noice.

[@d-a-n-g-89]

H Beams look exactly like I Beams, but H Beams have the same thickness in the flange and web, and are commonly used in vertical orientations where the loads are applied parallel to the beam length. The thicker web of an H Beam makes them more resistant to twisting. Whereas I-beams are typically horizontal, have thinner webs, because they are designed to only handle loads perpendicular to the length (top in compression, bottom in tension)

[@Gravvvyyy]

And....Another thing I've learned today!

[@ThatBum42]

Funny, I figured it was because someone didn't like the sound of I-piles. Like, a pile of eyeballs.

[@PeterEdin]

Then there's the O beam....hang on, that's a pipe 😅

[@meadow-maker]

I think you'll find iBeams have internet access.

[@LTDunltd]

Also I beams have a tapered flange to web.

[@ElectroBOOM]

I didn't know I wanted to know about piles until now!

[@SgtTibs]

No Preparation H required!

[@DudeRandom]

Me neither however I did enjoy learning the different types of piles

[@quietq1631]

Ooh electrical engineer looking at a video meant for civil engineers?

[@xileets]

"Piles of fun." I died. They had my funeral already. I just sank right into the ground.

[@jondavies261]

I have had an ongoing pile problem for years #bumholeproblems

[@akashx]

Bridges don't sink because they know how to swim

[@jasonbernal9348]

Exactly!

[@alysonbusatto1838]

Touché!

[@gamev.284]

dude. 💀

[@josechemartinez5036]

Facts

[@GooogleGoglee]

Thank you for the TL;DR version! Appreciated

[@wingsman13]

I’m a Construction Inspector Supervisor in PA and my current project is a 1100’ long, 4 span steel girder structure that spans a deep ravine and creek. We have a little bit of everything on this project, including Micropile, Drilled Caissons and Steel Piling. Each installation method has extensive testing involved such as Tension and Compression testing for the micropiles, CSL or Cross Sonic Logging testing for the Caissons and Dynamic Load Monitoring for the Driven Steel Pile. Pretty cool stuff!

[@Lone_Wolf_91]

Wow😮

[@mmseng2]

"The purpose of a foundation is to _not_ move" Grady spittin' the hard truths we all need to hear.

[@kevinsaluague009]

The most important thing is to keep the most important thing, the most important thing, and that is the "foundation"

[@aaqilian5.085]

dumb. Real dumb

[@DyslexicMitochondria]

Broken bridges annoy me. I just can't get over them

[@JustinLebo-d3t]

Broken bridges really put a gap in your plans.

[@balaam_7087]

If only there were some means of connecting these two comments

[@jessicatymczak5852]

You didn’t 🤦‍♀️

[@jpfidalgo7]

Underrated comment on overrated bridges!

[@GamingBren]

No one really cares about the river. It’s just water under the bridge

[@CarlosValeraLeon]

"imagine pouring a smoothie at the bottom of a pool. Let me show you what I mean" I cannot understate my disappointment that there wasn't a smash cut to Grady pouring a smoothie at the bottom of a pool XD

[@WackoMcGoose]

"This is me, pondering the life decisions that led up to me holding a giant syringe full of bentonite slurry in my garage." this episode had a _lot_ of brand new sentences

[@kaboom4679]

I cannot say how well it would work if poured onto the bottom . I CAN however tell you that one poured on the TOP , especially in close proximity to a group of distracted bathers just talking away and completely oblivious to all else ( for a moment anyway ) , is spectacular beyond your wildest imagination . I recommend chocolate , the darker the better , and , leave it in the full sun for 2 hours or so , prior to the experiment .

[@mastershooter64]

Me too D:

[@dragon_nammi]

​@@kaboom4679 This is diabolical.

[@chapablo]

His wife would Throw him into a cement mixer.

[@Mrcheesebumble]

Bridges don't sink because engineers secretly put thousands of pool noodles in the support columns.

[@OndrieDrake]

You are not supposed to tell anyone....

[@Mrcheesebumble]

@@OndrieDrake it's time the people know what keeps their "precious" bridges alive

[@RealJustinWillock]

I can’t believe you would just spoil the ending like that:(

[@foobar9220]

Actually, the concept is not as ridiculous as it sounds. Where I used to live, there is a bridge that uses a kind of styrofoam in its foundation

[@Mrcheesebumble]

​@foobar9220 huh. Can you expand on the use case? Maybe share the name of the concept so I can look into it? That's interesting.

[@dandandan18]

I'm still a student in civil engineering, and your channel has helped me a lot through the years. It's the only channel I've found almost exclusively for civil engineering making feature videos and content that are high quality and made with the non-engineering audience in mind. Honestly, I turn to your videos to understand a lot of concepts and principles on civil structures. I can't blame our professors for not delving deep on these aspects because of the limited lecture units/ hours, and it gets so busy that you have to prioritize learning the hard maths over the art of designing structures. It's a shame that my university has one of the biggest and oldest libraries in my country but I can't check all the books I want to consult. So your content are really incredibly helpful and very much a delight to watch. I hope I'll find somewhere to buy or borrow your book soon. Keep being awesome!

[@krox477]

How you're planning to enter the industry

[@adityarathore2036]

Bridges dont sink , bihar laughing in corner.

[@yashwanthkanamala]

Sinking is different The bihari bridge failed and collasped

[@Harshit-n5w]

I think Bihar is not laughing but crying tbh

[@westlarper]

grady the only guy who can get me to watch a 17 minute video about bridge foundations

[@aftersexhighfives]

And I'll never engineer or use a pile driver 😂😂😂

[@JediSentinal]

Seconding this!

[@davidfalterman8713]

“skin friction” and “shaft resistance” did give me a giggle, I have to admit….

[@General12th]

peepee

[@mphRagnarok]

can somebody explain this to me

[@Colorado_Native]

​@@mphRagnarokAsk your wife, or girlfriend. Or both and see which gives a better answer.

[@roderickcampbell2105]

@@Colorado_Native This very true. I would suggest asking your wife and girlfriend at the same time is unwise.

[@digitalchaos1980]

Don't forget "vibratory head" around the 4:16 mark 😆 😆

[@rmhbernoff]

I'm here for all the people who are just learning that "pile driver" is not just a wrestling move.

[@timseguine2]

It's almost like they named it after something

[@mdrzn]

as a non-english native, I'm 32 and I just learned what it means! lol

[@Dude-Smellmyhelmet]

All named after the car audio speaker brand.

[@aval1998]

My girlfriend got upset with me when she saw the rental equipment get dropped off after asking me to "pile drive her." I dunno why, though?

[@lucifer4844]

I'm here for all the civil engineers who are just learning that pile driver is a wrestling move.

[@aviationclub2637]

0:38 What you lookin Bro? 😅

[@crewrangergaming9582]

That fish got me rethinking my life choices 💀

[@SCUUZEM3]

Bro that fish was ABOUT it😂 he didnt back down at ALL

[@zachrichardson5581]

I'm a CAD drafter (6 years rebar detailing and now about a year and a half doing pre cast/stressed) and I've done a lot of shafts & piles during bridgework. Loved them because they're almost always easy, repetitive and made my end of year weight report look good to the bosses. It's really cool to see different perspectives on stuff like this that I have a decent understanding of but can learn more about the "why" behind the engineering of certain aspects. Plus the info graphics style animations combined with the at home demo stuff really helps explain things. Great video.

[@paulandersbullecer3152]

Do you just pretty much draw the sticks underdround and send numerical data to the higher ups?

[@zachrichardson5581]

@@paulandersbullecer3152it's partially like that. When I was detailing rebar I was making shop drawings to aid our placing team on the job site. Essentially a recreation of the strucural/architectural contract drawings that are provided by the general contractor from the EOR (engineer on record) that specifically highlight our scope. What I'm doing now is very similar except my drawings go directly to the fab shop to produce the pre cast products as well as to the contractor for their field needs.

[@noeraldinkabam]

Amsterdam is build on wooden poles. A lot of older houses in the Netherlands are build like that. Due to groundwater depletion the foundations of those houses are now having problems because the poles that stayed wet and therefor didn’t rot now do (rot)

[@DyslexicMitochondria]

Speaking of the dutch, Do you know how copper wire was invented? Two Dutchmen saw a penny on the floor at the same time.

[@kenbrown2808]

there is a housing development in my area where the better built houses have had friction piles driven into the ground, and then the concrete foundation poured on top of them.

[@Jessica-w1o]

@@DyslexicMitochondria haha gold

[@ZackRToler]

I remember watching a show, I think impossible engineering or something similar, on the Science channel some months back about the complications of making subways in Amsterdam. And part of the complications was not just how soft and wet the soil is, but how so many buildings have the large wooden stakes that you mentioned. They not only needed to dig even deeper to go under the poles, but also make sure they're not weakening the soil that those poles rely on. So, from what I remember, they had to slowly dig their way while putting in walls and ceiling to enforce the soil in a way. Though this led to complications with water flooding the tunnels a few times. At least this is what I remember atop my head. So sorry if I got some details mixed up or wrong.

[@bartbjorri9502]

Wooden piles are still used a lot in the Netherlands, mostly with a two meter concrete pile on top. Wood is a lot cheaper and lighter to transport and handle. As long as the wooden part stays under groundwater level (most of the time) they won't rot.

[@dj_laundry_list]

Your second channel, Impractical Engineering, should have a video on why bridges sink

[@Lorcan.oshanahan]

This should be a thing, completely ai generated garbage based on what is on the main channel

[@mostlyvoid.partiallystars]

Best comment. 🎉

[@fcrick]

Or on this channel. Some bridges DO sink.

[@Dracomancer273]

​@@fcrick And some bridges float!

[@76844]

That's a simple short, cause gravity duh

[@mercoid]

Your overall production quality is excellent in nearly every aspect. Animations, voice level and quality, music.. not too loud, well chosen stock footage, editing….. etc. etc… Very impressive.

[@pooroldpedro]

everything apart from not buttoning the button-down colar. I'm surprised all the engineers reading this aren't driven mad by it :-)

[@laura-ann.0726]

Great video! I was a draftsman and engineering tech in the CalTrans Office of Structure Design in Sacramento for 15 years, 1991-2006, and spent thousands of hours working on bridge and retaining wall foundation plans and Logs of soil test borings. The only foundations I can think of that have to bear heavier loads than highway and rail bridges are dams, especially the "big guys": Hoover Dam, Glen Canyon, Grand Coulee, etc. And maybe skyscaper office towers built on soils where bedrock is too deep to be reached directly by the building foundation. When the new East Span of the San Francisco-Oakland Bay Bridge was being built a few years ago, I was out at the jobsite one day on a field trip with some of our design section Engineers, just sightseeing (our section didn't have any direct involvement with the project), and we got to watch piles being driven for one of the bents on the Skyway portion of the bridge. The "Skyway" was that part of the bridge that didn't have to be raised high enough for ships to pass under, so it was a cantilevered pre-fab box girder, running from the east abutment on the Oakland shore, to the east end of the new Cable-stayed span. The mud under this part of the new bridge was very deep: the depth from the water surface to bedrock was 350 feet at the center of the channel between the Oakland shore and Yerba Buena Island, so several of the Skyway bents had to be built on pile caps supported by 36" diameter cast-in-steel-shell pipe piles that were 300+ feet long. These consisted of sections of 36" pipe, Schedule 40 I think, that were somewhere between 20 feet to 40 feet long (I don't remember the exact number). The first section to be lowered from the transport barge by a crane had cap plates welded on the ends to keep water and mud out, and was long enough to reach from the mud line to several feet above high-tide water level. This was lowered to the mud and allowed to sink in several feet under it's own weight, then the crane operator would tilt the pile to a pre-determined angle. The "footprint" of the piles as they entered the mud was substantially wider than the pattern of the tops of the piles at the pile cap. I seem to remember there were 12 piles under each pile cap, and 2 pile caps per bent. As the pile reached equilibrium and stopped sinking deeper under it's own weight, it would be driven a bit deeper, then a new section of pipe field-welded on and the driving would continue, with additional sections of pipe added, until the calculated bearing capacity of that pile was obtained, or "refusal" was reached. A rebar cage would be lowered in, and the pile back-filled with concrete. One of the engineers mentioned to me that the cost of the foundations alone - the piles and pile caps - for the Skyway was nearly half the total cost, and maybe a bit more than half. The whole project - the cable-stayed span, the skyway, and the approaches and abutments - eventually totalled out to over $7 billion, I heard, so we're not talking penny-ante level civil engineering here. The Burj Khalifa didn't cost nearly as much as this bridge, I think. The entire original SFOBB, both the east and west spans, only cost $75 million in 1936, so I guess there's no escaping the boogeyman of Inflation even if you are The Federal Government paying the bills.

[@szurketaltos2693]

US infra costs are insane in general, and have been for decades.

[@Bobo-ox7fj]

This is an excellent comment and very useful, tarnished only by the mention of inflation right at the end. There is one very simple tactic to combat inflation: do not add/replace currency at a rate greater than your economy grows, adjusting for the longevity of your coins and notes. The downside to this (if you are a government or bank) is that people will be able to keep what they have earned and will eventually be able to stop working, lowering taxation revenue and/or deposits.

[@bishnukumaradhikari3564]

Except Bihar

[@RiVer-Parish]

My 11 year old son loves your channel. A kid can learn a lot from watching your videos.

[@HildeTheOkayish]

So can adults like me :p

[@patrickw9520]

Hell adults can learn a lot lol 😂 Legit, this channel has helped me with some tasks on my farm, even just with driveway and culvert maintenance😂 Legit, this is a channel any homesteader would benefit watching.

[@RiVer-Parish]

@patrickw9520 That's true

[@andybaldman]

He can learn even more by going to college someday. Watching videos is entertainment, not actual learning.

[@pizzagroom6221]

@@patrickw9520 the stuff I learnt about how culverts/dams/shorelines work from this channel is truly A-tier

[@pizzagroom6221]

I love the thought that Grady set up the hammer and nail demonstration, failed, and just ran with it

[@timhansen3514]

Knows his audience.... 😉

[@pvic6959]

failed? I think he succeeded in a different way :p

[@cycle_path]

Having piles of fun. Love the pun!!

[@jimvee4528]

I didn’t go too deep into piles in that video

[@flixri726]

The pile driver with the vibrating head got me

[@Datsyukiandeke]

5:32 this is what the wife tells me when I've gone too far, and I then say "i have reached refusal"

[@Brain_quench]

@7:38 The battered pile is designed like tree roots. More of engineering catching up to nature & God's design.

[@jaypolas4136]

Yes!

[@VisioGuy]

Somewhere in the Port of Tacoma's archives are books and books of my beats-per-foot logs that give an idea of the relative skin friction for each of thousands of piles supporting the then-new pier. That was my big engineering internship - counting and recording pile-driver hammer blows all day long. Things I learned that Summer: there's such a thing as "waterproof paper" - the pencil would still write on it, even when the clipboard was out in the rain! And pre-stressed concrete is pretty cool!

[@charleshanfman]

Some of the differences are H piles are made of different steel typically A572 Gr. 50 instead of the A992 for a wide flange beams. H piles typically have equal thickness flanges and webs also equal depth and flange width dimensions.

[@jasonhink226]

Those grades are technically different but practically identical. Most stuff coming from domestic mills is certified to meet the specifications for both grades

[@jothain]

Plus to my knowledge H profiles are square in dimensions. I profiles aren't.

[@kindlin]

The dimensions are the critical part to that, the steel is mostly incidental nowadays, as Jason points out. There are reasons to spec one grade over the other, but really, if they're all dual or quad certified anyways, it's all good steel. Just don't go to china.

[@fiskurtjorn]

3:34 I once saw a construction site where piles were driven into the ground. There was a peat layer between two layers of sand. It took the machine a good amount of effort to drive the first four meters or so. Then it sank by itself until about four meters left. Those last few meters took a lot of effort again. Watching this for a morning gave a lot of insight into how the peat was undulating on the bottom more than on the top.

[@kindlin]

Yeah, peat is literally the worst type of soil to build on, you are NOT ALLOWED to make a bearing-type _shallow foundation_ on peat soil, unless it's nothing more than a backyard shed or something else equally small and unimportant.

[@Alexanderofthe9th]

5:11 if my pile starts feeling some friction it's time to change position or add lubricant

[@timhansen3514]

You brought back memories of the construction of CA118 through the San Fernando Valley. When I was a youngster CalTrans needed to span a concrete storm drain channel and the 2 streets diagonally. We lived two blocks away. Once the pile driving started, it seemed to last forever. One the plus side, when the city moved houses off their foundations to make room for the freeway in the 60's we took the banana seats off our stingrays and put 10 speed saddles on, cut down the bars and BMX was invented. All manner of ramps and bumps available in the newly emptied lots. 👍 Thanks for the videos!

[@A1BASE]

My favorite story about the Coronado bridge you show in the thumbnail is how it got its iconic shape, because it wasn't designed that way originally... The story goes that at the time it was being built there were substantial federal subsidies for bridges over a certain length, but the original plan for a straight bridge from downtown San Diego to Coronado wasn't quite long enough to qualify, so the city just tacked a bit of a curve and hump onto the design to JUST meet the funding requirements, and by accident ended up with an iconic piece of infrastructure. X)

[@bobstopthat]

I don't think you should bet too much on this story. the more logical explanation I've heard is that to get the height over the bay required by the navy, while maintaing the maximum roadway slope and minimum vertical curve required for sight distance, the curved horizontal geometry was chosen to provide the total lenght required while minimizing the height of the roadbed at each side of the bay.

[@Appl_Jax]

@@bobstopthat That was my thought too. I've crossed that bridge more times than I remember, it seemed fairly obvious to get the bridge high enough to clear the ships that would need to pass, they would need to build it that way.

[@jimdennis2451]

When I saw the Coronado and "Why Bridges Don't Sink" I just remember being told that the two darker blue spans in the center floated, so if the bridge was blown up, the fleet could still get underway.

[@julieinthenorthwest4594]

@@bobstopthat @A1BASE is wrong. and you're correct. I can remember taking the ferries over to Coronado and when the bridge was planned. The Navy was actually against the bridge worried it could collapsed. The naval base was (and is) south of the bridge and would need to pass under the bridge to get to the Pacific. They gave in and agreed to the bridge only if the bridge was 200 feet or taller letting their ships pass. It had nothing to do about federal subsidies. On another note, it was sold to the public that the toll would be only temporary until the bridge construction costs were covered. Of course, the toll kept going way pass after the construction costs were paid and finally ended early 2000s. IIRC it 60 cents each way.

[@dragon_nammi]

That bridge has zero pedestrian access which is a shame. Although I suspect the residents of the peninsula wouldn't really support the idea...

[@RyanGribble]

Grady, i was a concrete pump operator for several years and worked on many bridges. On company used a basketball to plug their tremme pipe to get concrete under the water in the casings. As the casings filled, one guy would climb down to recover the ball. I did have one critique about the concrete underwater as we use admixtures of bentonite and silica fume to make concrete "water proof" so that it doesn't dissipate underwater.

[@mastershooter64]

Lmao what? that's so funny a basketball

[@ginajanee12]

Do they use a basketball as a weight?

[@RyanGribble]

@@ginajanee12 no not as a weight, as a means of keeping water from ingressing the tremme pipe. It just so happened that a basketball was the perfect diameter.

[@gijskramer1702]

Should have played the audio of the driving to give people an idea how terribly loud it is. Love the video as always!!

[@kaboom4679]

Especially the one that is essentially a big single cylinder diesel engine . The driver hitting the post compresses a piston in a bore , where fuel is injected , and , the explosion instead of driving a connecting rod to turn a crankshaft , is directed downward into the pile . That's why the one driver was belching clouds of black smoke on every strike . They are very effective , and , AMAZINGLY loud .

[@DoggosAndJiuJitsu]

Bridges don’t sink because they’re above the water 🤷🏻

[@DeepKumar.]

"Skin friction", "Shaft Resistance", "Drilled Shafts", "Drilled Holes", "Small Holes" Okay I'll see myself out...🤣

[@misseselise3864]

we have the humor of a fourth grade boy and that’s ok!

[@extragoogleaccount6061]

Have you seen the announcement of Saudi Arabia trying to build a 2-kilometer tall sky scraper? I’d like to see a video about the engineering issues caused by super tall buildings. I think you covered some related issues over time, of course, so I’ll see if one exists that I missed. But the piles discussion made me think of this proposed skyscraper.

[@Leadlobotamist]

Before I moved out of Florida I got to see a lot of the work being done to rebuild the Howard Franklin bridge. The pile driving was pretty extensive but everytime I'd cross the bridge every, say, three weeks, they'd make about a foot of progress for the better part of 100 piles. It's slow work but pretty cool seeing these massive chunks of material sticking out of water. Like some modern art project.

[@robertheinkel6225]

Do you remember when the support piling for the elevated crosstown expressway, between Tampa and Brandon, sunk one night? It was placed over a sinkhole that gave way.

[@laynedouglas5105]

Correction to one of your statements - I beans are different from H piles. I beams are also different from H beams. I beams and H beams have different cross sections. Love the channel.

[@DanielRucci]

Don’t be such a stick in the mud.

[@plwadodveeefdv]

But what he said is he doesn't know why one is called "H" and the other "I"

[@DanielRucci]

@@plwadodveeefdv I was making a joke, LOL. Get it? “Stick in the mud?”

[@Blezerker]

4:14 I should call her…

[@karmaisanillusion7307]

You’re sick for that😂

[@TheFranksoz]

Bridges don’t sink because they’re secretly filled with helium balloons.

[@_MikeJon_]

A video on ancient engineering would be awesome

[@ssmith7074]

A whole video about piles and not one joke about Gomer. Such a missed opportunity.

[@kaboom4679]

Or medical references

[@bobcoats2708]

Before Grady’s time I guess

[@kenbrown2808]

I accidentally came into possession of a geological survey book for my area, and one of the noteworthy things was a ground density graph formed by driving piles, and recording the distance per strike. most noteworthy was zones underground where the hammer pushed the pile down through soft ground; underneath zones where it was hammered down.

[@peterfireflylund]

Should have been a villa in France. Better luck next time!

[@kenbrown2808]

@@peterfireflylund why would I want a geological survey book for a villa in france?

[@lightningdemolition1964]

​@@kenbrown2808I think he means it would be better if you accidentally came into possession of a villa in France.

[@csabamagyar3244]

It was great to see my home home city's bridge at 7:10 -- Budapest, Margaret Bridge (Margit-híd), first opened in 1876, then destroyed in WW2 and re-built, re-opened in 1948. The tram line (No 4-6 tram) that runs over it carries possibly the most passengers/day in the world.

[@LadiesFS2024]

WHo else watch this to the END? ❤❤❤❤❤❤❤❤❤❤❤❤

[@Trainsaregreat365]

Me

[@BrettW]

2 minutes in and the puns are already being piled on.

[@dirkus3722]

The little hardhat and glasses on the post driver were top tier.

[@TubeTimeUS]

There were Neolithic pile dwellings built on Lake Zurich in Switzerland around 4000-7000 years ago (now part of a UNESCO world heritage site). my grandfather had a (presumably 19th century) painting showing the remains of the piles sticking out above the water. Since then, the water level has risen and the piles are all underwater.

[@cfdtv1]

My favorite pile is Gomer Pyle!

[@2smoker64]

And then there was private Pyle. He couldn't have jelly donuts on account of his weight problem.

[@justlisten82]

My wife knows all about "shaft resistance" 😂

[@EsveePaulFedSlayer]

Must be from her being bone dry lol

[@theandrogynousmisogynist]

And withstanding great loads

[@ColinRichardson]

I love the pile driver has its own hat and glasses

[@asgdfgify]

4:09 "Nailed it!"

[@HDL_CinC_Dragon]

Beat me to it!

[@Pentti666]

I spit my noodles all around when Grady hit the nail :D Even though I knew from the beginning that he ain't gonna hit it like that

[@graham1034]

I hate pile driving so much. I bought my apartment about 10 years ago and since then there has been pile driving for about half of that time as new towers have been built on all sides. It wasn't so bad for the first 5 or so years, but then I started WFH in 2020 and it is brutal. I have to wear noise cancelling headphones for 40 hours a week just to stay sane. And god forbid I want to sleep in past 8am one day.

[@paxdriver]

6:08 "in most cases you can just keep piling downward until you do" is that related to underground rivers or reservoirs or are there other factors? I'd love a video on subterranean geographic as it relates to structural/geotechnical engineering! ❤ Just an idea lol love the channel, thank you for all the years of great work! You've really been a huge help in my life gain work experience while I was bedridden due to chronic health issues throughout my life. Instead of eroding on a gurney every time I came back capable of inspiring confidence in my professional life after months of recovery. Home projects like patios and landscaping I could even confidently do well myself by understanding how all these things work. This channel didn't just keep me stimulated and professionally viable in trades as a property manager and expeditor really helped me learn new industries quickly and build rapport despite lengthy medically force hiatus. I'm really and truly grateful for this channel, thank you for all the hard work. Your character is inspiring and you're a fantastic teacher.

[@steamfitter5269]

These are, by far, the best videos on KZbin! Thank you for all of your content

[@BertNielson]

Had a friend that told me about the piles that support the SeaTac to Seattle elevated tram. They rely on the friction of the soil because they coulddn't drill deep enough to hit bedrock. He cautioned that in the event of a large enough earthquake, the piles would sink as the soil essentially would liquify.

[@naamadossantossilva4736]

Did they at least make the part where people would be buoyant?

[@BertNielson]

@@naamadossantossilva4736 nope. It's all concrete and steel. It's elevated track, so buoyancy wouldn't do anything about the fall.

[@robertheinkel6225]

When Flagler built his railroad in Florida, across the swampland, the pilings just kept going down. He determined if he stacked three pilings on top of each other, it would support the railroad. The friction on the pilings worked well supporting the line.

[@BertNielson]

@@robertheinkel6225 Listen, lad. I built this kingdom up from nothing. When I started here, all there was was swamp. Other kings said I was daft to build a castle on a swamp, but I built it all the same, just to show 'em. It sank into the swamp. So, I built a second one. That sank into the swamp. So, I built a third one. That burned down, fell over, then sank into the swamp, but the fourth one... stayed up! And that's what you're gonna get, lad: the strongest castle in these islands.

[@Hearstbane]

​@@BertNielson Ah hell what is this from again??

[@cashflow68]

Much love from San Francisco. Enjoying my view of the Golden Gate Bridge

[@jacklarue7049]

This is an unbelievably excellent documentary. I have only a very base knowledge of civil engineering, the complexity of bridges & their technology, plus the steps needed to complete one from scratch. Not only did you break down difficult to understand concepts to a level where someone with limited knowledge on the subject can easily learn a lot, you had some great visual examples of just about everything. I’m hoping to see a lot more quality uploads on your channel and will be heading over to your main page to check out your past work. Thanks for this, _THIS_ is what KZbin is all about!

[@Steaphany]

I suggest you do a video on the History associated with the construction of the Brooklyn Bridge tower foundations. From my explorations, one tower sits on bedrock, the other tower sits on sand. The foundations were excavated by hand manual labor with a pressurized work area that contributed to workers suffering from the Bends when they exited the workspace.

[@missamo80]

5:22 The glasses and hard hat on the driving tool are amazing. 😂

[@BijaySigdel]

8:11 Thats what she said😂😂😂😂

[@CaptTerrific]

A wonderful video... but now I have even more questions about Millennium Tower than I did before watching :D

[@Trixtah]

He's got a whole episode on it

[@robertheinkel6225]

Apparently nobody told this to the engineers when the new elevated crosstown expressway was built In Tampa. One morning before the expressway was opened, one section sank, taking the roadway with it. The blame game began on who was responsible. After it was repaired, all the rest of the pilings had to be individually tested by a thumping truck.

[@tbix1963]

Thanks for sharing your thoughts, ideas and videos. My favorite memory of a pile installation was of a mall being built when I was in college. They started driving a pile. Every day for about a few weeks they would add another pile in the exact same place. Eventually they took the pile driver away and just left the pile sticking out of the ground. As I drove by every day I eventually noticed it was still going in on its own. After a few weeks it was totally gone. When the mall eventually opened up they stated the reason for the massive parking garage under the mall was for buoyancy since the ground was so unstable that they were unable to put in piles for the foundation. I often pondered after that if the mall ever goes out of business it will be interesting to see if the garage fills with water and sinks the mall.

[@XavierMathewsEntertainment]

I was too immature for the verbiage in this video. 😭🤭😩😂

[@eddrm4685]

Gomer Pyle!

[@salmanhendershot782]

I'll have to apologize up front for this joke..... My favorite pile is private. I'll see myself out. Wow.... as I'm about to post I figured out this joke has another layer.... and another... lol. Thanks for the incredible interesting engineering content. Always amazing.

[@natetallman]

4:56 and on is gold!

[@Aby7799]

Piles: Humans ❌ 🥶😵 Bridges ✅ ❤😊

[@jandraelune1]

Roman concrete was used directly in the water, was even designed to not fully cure leaving pockets of uncured concrete when cracks form, those pockets cure allowing the structure to repair it's self.

[@lamppostwillie]

And amazingly with mineral intrusion over time, it gets stronger.

[@fredinit]

Not much different that modern high-quality hydraulic (Portland) cements. It's not that the Roman stuff is 'better'. It's just been around a long time - a.k.a. survivor bias.

[@michaelmcmullen354]

@@fredinit Not exactly. Modern concrete is tested for strength, and usually not paid for until that strength is achieved. Also the strength is often needed for subsequent stages of construction. Therefore it is ground finer to set faster and usually has a chemistry to reach strength faster too speeding both the flow of money and the work. It also gets hotter when it sets and can shrink and crack more. So it is better from a financial viewpoint, but not all structural viewpoints.

[@heitorbernardes7977]

Here in Brazil our 4th generation Synchrotron light source (Sirius) has an array of piles as a foundation. Now I can't remember in details the depth... And I know they had to build an ice factory for the concrete, again can't remember if that was for the floor or dor the piles (or both)... I just know that the inner floor is detached from the building's walls.

[@vaibhavhayaran]

Thank goodness I didn’t choose civil engineering. As much as it fascinates me it’s extremely hard and I’m sure if i did choose civil engineering in college id be failing all the exams. Massive respect for civil and mechanical engineers!

[@prestidigitationer9888]

My favorite flavor of pile is a pile of donuts

[@dukeofgibbon4043]

4:15 One of the cool things about the pile driver you showed is it's basically a diesel engine. A lot of pile drivers are an open cylinder; an engine that doesn't need valves, that inject some fuel to use the compression of the falling weight to both drive the pile and create a power stroke that propels the next strike.

[@WartimeFriction]

Fascinating

[@VictorQuesada-bl1xk]

That's so cool, thanks!

[@ilkerkarapinar]

How about jet grouting columns? They are very effective on most soil conditions. Very high surface friction. It will be very fun to watch your studio applications. Well done, love your channel

[@mrcraftiest]

The essence of a bridge is not only a passage over water reservoir but also passage below itself. That gigantic syringe. Nice micro-implementations in the garage.

[@Bilarf]

Opening shot of Pittsburgh is perfection

[@paulweiler8967]

I am thankful for this but it's also way way wayy too long of a video, you could easily explain in 5-8 minutes also

[@isaacplaysbass8568]

Utterly fascinating. I've been enjoying seeing the construction processes over at StarBase Texas via many of the youtubers that document the developments. Thank you Grady :)

[@Capxam]

I was not ready for the bearded grady jump scare

[@anthonystramella7018]

There is a skyscraper in New York that is starting to lean significantly because of Pilling miscalculation

[@Thelegend-z7d]

Ohh... THIS GUY... PILES OF FUN... Did you here that? This guy is on FIRE

[@harryd9782]

When I lived along the northeast coast all the houses were built on pilings. They were creosote-treated poles. They would keep adding pole on top of pole until they hit bedrock. They don’t rot at all if they remain underwater.

[@cornfarts]

Just dont try and make moonshine in a little cave supported by creosote covered telephone poles

[@jfmezei]

The Indian River bridge on Delaware shores 38.608259786025904, -75.06323136068384 between Rehoboth and Bethany Beach had a problem: it was right where the river flows into the ocean and the stronger than expected tides, causing water to flow an and out, eroded the sand at the base of pillars to a point where the pillars started to lose their support. It was replaced very quickly circa 2010-2012 with suspension bridge with no pillars in the river and 2 large towers on each side or river.

[@Xecoda]

I feel like a Llama wants to fall off of the thumbnail bridge

[@mafarnz]

On my railroad the bridges are mostly creosoted timber trestles. One of them in Kennedy Ford Idaho crosses the Palouse River at a location where the bedrock, in this case actual solid basalt, is very shallow. The wood piles rest on top of the rock. This creates a problem when the river floods and water flows over the top of the bridge deck… wood floats! There have been a few recorded instances since the current bridge was built in the 1960’s of the bridge floating downstream a few feet during a flood. The old railroad company in the 60’s and 70’s would run big chains to bulldozers on each shore and pull it back into place! In the 70’s and 80’s a few of the upstream piles were replaced with steel H piles and that seems to have stopped the floating away issue. I’m still concerned about what will happen should we get another deck topping flood however.

[@scottzehrung4829]

When I was down in Biloxi, MS back in the early 80’s I saw my first pile driver used in construction of an elevated roadway. Was amazed at what looked like a single piston diesel slug riding up and down tracks aside the pile. Was mesmerized for awhile watching the progress, you could feel the rejection throughout your body from far away.

[@fredygump5578]

Just FYI, those are not "i" beams...they are "W" beams! W = wide flange.

[@PatrickBaptist]

Gravity? But how does spinning a ball a thousand miles an hour make gravity? I've never once been able to replicate any gravity, anything I spin just does the opposite of what gravity is claimed......

[@maw9723]

I'm not even an engineer and I find this channel super interesting. Muchas gracias!

[@RawDawgginnit]

Not once in my life did i wonder or care about this but somehow youtube recommended it and now im here watching

[@introvertlazyloner]

Well they sink and collapse in India, Even brand new one made by established companies

[@MyersMushroomsFarms]

Next time you need to do a drill out display try agar. 10-20g per 1000ml of water, boil pour and room temp cool. Makes a nice firm but transparent media.

[@arjunyg4655]

Can’t believe we got 14m28s in without mentioning the Millenium tower lmao.

[@morganrosenfeld5917]

Big Cement don’t want you to know Concrete is actually buoyant and floats on water.

[@mjt1229]

I've driven miles of piles over the past 25 years, timber piles, H-piles, prestressed concrete piles, pipe piles (steel and concrete)... Toss in drilled shafts and micropiles, and I've inspected most of the bridge foundations used today. We still use spread footings near my home in SW VA wherever we find competent rock. I know a lot of folks in the business hate pile driving, but other than deck construction, it's my favorite part of bridge inspection.

[@xsbxsbxsb]

The relative dimensions of I-beams and H-beams differ. H are thicker.

[@ZaximusRex]

I-Beams vs. H-Piles, iPile was likely already trademarked by Apple lol

[@sanfordgfogg]

Structural Steel beams are categorized as I or W (wide flange) beams. It is these Wide flange beams that are often described as an H versus an I, and the primary difference is that the flange is wider, and is not actually I beam. The differences in the shape of wide flange and I-beams are components of the materials loading calculations, strengths, friction, load bearing capacities, etc. I-beams specifically are best suited when side loading is within engineering tolerances and weight/size restrictions allow compliance. In driven piles, it would not be good for your pile to look like ribbon candy in the ground, and thus a wider flanged beam supports the pile to keep it's shape better. Your channel would be great to demonstrate that with mock-up models that could demonstrate this effect.