Why Bridges Don't Sink
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- Опубликовано: 1 июл 2024
- 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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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!
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
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.
My favorite pile is the grounding rod
0:42 That is Mumbai. Noice.
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)
And....Another thing I've learned today!
Funny, I figured it was because someone didn't like the sound of I-piles. Like, a pile of eyeballs.
Then there's the O beam....hang on, that's a pipe 😅
I think you'll find iBeams have internet access.
Also I beams have a tapered flange to web.
I didn't know I wanted to know about piles until now!
No Preparation H required!
Me neither however I did enjoy learning the different types of piles
Ooh electrical engineer looking at a video meant for civil engineers?
"Piles of fun."
I died. They had my funeral already. I just sank right into the ground.
I have had an ongoing pile problem for years #bumholeproblems
Bridges don't sink because engineers secretly put thousands of pool noodles in the support columns.
You are not supposed to tell anyone....
@@OndrieDrake it's time the people know what keeps their "precious" bridges alive
I can’t believe you would just spoil the ending like that:(
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
@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.
“skin friction” and “shaft resistance” did give me a giggle, I have to admit….
peepee
can somebody explain this to me
10:19 So now I have an open hole.
@@mphRagnarokAsk your wife, or girlfriend. Or both and see which gives a better answer.
@@Colorado_Native This very true. I would suggest asking your wife and girlfriend at the same time is unwise.
Bridges don't sink because they know how to swim
Exactly!
Touché!
dude. 💀
Facts
Thank you for the TL;DR version!
Appreciated
Broken bridges annoy me. I just can't get over them
Broken bridges really put a gap in your plans.
If only there were some means of connecting these two comments
You didn’t 🤦♀️
Underrated comment on overrated bridges!
No one really cares about the river. It’s just water under the bridge
"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
"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
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 .
grady the only guy who can get me to watch a 17 minute video about bridge foundations
And I'll never engineer or use a pile driver 😂😂😂
Seconding this!
I love the thought that Grady set up the hammer and nail demonstration, failed, and just ran with it
Knows his audience.... 😉
failed? I think he succeeded in a different way :p
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)
Speaking of the dutch, Do you know how copper wire was invented?
Two Dutchmen saw a penny on the floor at the same time.
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.
@@DyslexicMitochondria haha gold
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.
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.
I'm here for all the people who are just learning that "pile driver" is not just a wrestling move.
It's almost like they named it after something
as a non-english native, I'm 32 and I just learned what it means! lol
All named after the car audio speaker brand.
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?
I'm here for all the civil engineers who are just learning that pile driver is a wrestling move.
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.
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.
Your second channel, Impractical Engineering, should have a video on why bridges sink
This should be a thing, completely ai generated garbage based on what is on the main channel
Best comment. 🎉
Or on this channel. Some bridges DO sink.
@@fcrick And some bridges float!
That's a simple short, cause gravity duh
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.
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.
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)
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.
@@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.
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.
@@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.
Having piles of fun.
Love the pun!!
I didn’t go too deep into piles in that video
The pile driver with the vibrating head got me
My 11 year old son loves your channel. A kid can learn a lot from watching your videos.
So can adults like me :p
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.
@patrickw9520 That's true
He can learn even more by going to college someday. Watching videos is entertainment, not actual learning.
@@patrickw9520 the stuff I learnt about how culverts/dams/shorelines work from this channel is truly A-tier
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!
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.
Those grades are technically different but practically identical. Most stuff coming from domestic mills is certified to meet the specifications for both grades
Plus to my knowledge H profiles are square in dimensions. I profiles aren't.
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.
The little hardhat and glasses on the post driver were top tier.
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.
Don’t be such a stick in the mud.
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.
My favorite pile is Gomer Pyle!
And then there was private Pyle.
He couldn't have jelly donuts on account of his weight problem.
Should have played the audio of the driving to give people an idea how terribly loud it is. Love the video as always!!
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 .
A whole video about piles and not one joke about Gomer. Such a missed opportunity.
Or medical references
Before Grady’s time I guess
A video on ancient engineering would be awesome
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.
Should have been a villa in France. Better luck next time!
@@peterfireflylund why would I want a geological survey book for a villa in france?
@@kenbrown2808I think he means it would be better if you accidentally came into possession of a villa in France.
"The purpose of a foundation is to _not_ move"
Grady spittin' the hard truths we all need to hear.
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.
Did they at least make the part where people would be buoyant?
4:09 "Nailed it!"
Beat me to it!
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
I love the pile driver has its own hat and glasses
5:22 The glasses and hard hat on the driving tool are amazing. 😂
My immediate hypothesis for "I-beam" versus "H-pile" is to provide a layer of disambiguating terminology in cases where multiple parts of a structure are very similar. Suppose you have a collection of two sets of very similar steel structural members which differ only in length; it seems intuitively easier to remember "8 meter I-beams and 8.5 meter H-piles" than to remember that "the 8.5 meter I-beams are piles and the 8 meter I-beams are for the above-ground structure". I would suspect that this is a factor in the difference in name; it creates a semantic distinction between the two.
Alternatively, this could be a case where someone was using standardized H-piles and someone else was independently using standardized I-beams, and when the two standards met and became used together the names were so thoroughly established that they didn't get unified.
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.
2 minutes in and the puns are already being piled on.
These are, by far, the best videos on RUclips! Thank you for all of your content
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.
One nice thing about H-Piles and pipe piles is that you can form a "soil plug" as you drive. Soil gets stuck between the flanges of the H-piles or in the inside of a pipe pile. This can almost make the pile act as though it's solid without using the extra material.
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!
Much love from San Francisco. Enjoying my view of the Golden Gate Bridge
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!
HECK YESSS more mini demos!!!
Gomer Pyle!
A wonderful video... but now I have even more questions about Millennium Tower than I did before watching :D
He's got a whole episode on it
this is brilliant. love that you keep on referring to the official documents. shows that you're thorough and invites all the supernerds to go further
As a San Diego native i appreciate the Coranodo bridge in the thumbnail. Fun to drive across.
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.
And amazingly with mineral intrusion over time, it gets stronger.
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.
@@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.
Hello world
Great video as always. Thank you
A perfect example of how pilings work can be demonstrated by something I learned in a WWII era heavy rescue class in the late 1980s. We made a gin pole and used three 1.5 inch steel pins by three feet long as an anchor in very loose sand. We drove the stakes about 2 feet into the sand about one foot apart and lashed them together and then use that picket as an anchor point for the gin pole to lift a 450-lb drum. When we were finished, you untied the lashing and the stakes very easily pulled out of the sand. One stake would not hold but the friction of the sand on the three made the anchor very strong.
it took me this long to learn what a piledriver actually is
Awesome as always.
Hey Grady, I just wanted to say that you produce some of the best educational content on RUclips. Always interesting, concise, with excellent clear presentation. Keep up the great work.
Great video, Grady!
9:00: Ah, yes, the classic Drilling 747, my favorite form of travel
Grady's pile driver having a helmet and glasses absolutely wrecked me 🤣
Grady, when we added a new building to our college out here in NE San Antonio they were putting in some piles the vibration was strong enough to knock my favorite Beatles poster off the wall. (Good news, my dean paid for the replacement poster). I totally get the disruption caution for installing piles.
When I was in college, they were driving piles for a new building next door. It was enough to shake the projectors hanging from the ceiling. At the time it was pretty entertaining.
Another absolute gem of a video!
Always excited to see a new video!
I’m taking a deep foundations class right now! Loved seeing the concepts I’ve learned in class reflected in the video, great job
I was planning on going rollerblading, but here I am learning why bridges don't sink.
Very pleased I watched. Gracias.
offshore wind turbines could be a cylinder for buoyancy, pump ballast inn for strong winds and pump ballast out for light winds
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.
I've been waiting literally years to understand this. Thanks for posting such a great video. I appreciate it!
Amazing video! What makes it so perfect is the experiment and the animations (and the content off course!), just wonderful and it makes it easy to understand!
Grady, I just love that jaunty intro/outro music. It perfectly captures the positive enthusiasm of the channel and its host. Thanks❣️
Very good. Thank you
I love that you have a little hat and glasses on your post driver.
Great vid I enjoyed it and learned a bit
i saw Pile live in 2019 in Seattle. my band was on tour from Alaska and had just played the same venue a few days before. they're my guitar player's favorite band so the lucky factor just enhanced the whole thing. they were amazing. highly recommend checking them out.
Something ive randomly thought about for years but not looked into, thanks Grady!
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.
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.
Great video
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.
Great watch Grady, cool to see you so high up in the trending list!
Thanks for covering a massive portion of my field! I mostly stick with shallow foundations, but sometimes, things are too big to put on spread footings!
Thanks for sharing this information. Love studying engineering structures
They also use them at intersections where ground settling is a concern. A lot of vehicles coming to a stop at a traffic light can increase the load at a point
thank you very much. your explanations are clear and the subject is fascinating. you're an excellent teacher.
This is the stuff discovery used to produce back in the 90s/20s. But yours is even more pleasant to watch!
Great content! Super polished but you leave in just enough "mistakes" to keep it interesting and real.
I've got a question on the Battered piles. When driving them deeper how do you know if they broke? Same question with the pile cap? With the battered piles I'd assume after awhile they would break off the cap?
Usually it's not an issue, but there is a test called a Pile Driving Analyzer that can be done during pile driving to check capacity and to make sure it's not broken. It's basically an accelerometer and a strain gauge attached to the top of the pile. Software analyzes it in real time.
Great vid, very interesting! I so appreciate your knowledge & enthusiasm for bringing those of us with a layman's interest along … showing off some of the clever details of your field. A truly excellent way to spend 15 minutes, deeply appreciated.
I worked 19 years in the pile driving business 😎 excellent video!
Every day I've been driving past a new construction project where I've been watching them drive a series of piles into the ground.
It's interesting how you keep coming out with videos that just so happen to be about the very constructions projects that keep garnering my attention.
I'm so glad this channel exists, thank you for answering the questions I had as a kid Grady!
13:13 How do they ream the bottom of the drilled shaft??? Great video!
Interesting very important topic!
Just did a presentation about deep foundations a couple of weeks ago at my class. Engineering is awesome
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 :)
Good overview Grady. I do like your presentations
That was very amusing !
Lived across the street from a pile driving operation for a year. I swear I still hear it in my nightmares. Every second or two bang, bang bang, everything shakes, all day from 5am to 8pm. Not to mention all the dust, since it was for a bridge over the highway, earthworks was happening for the approach at the same time.
I enjoy construction, but not when they have no limits on noise, vibration, or work times.
Worked as a structural technician and the engineer designed piles for a house uphill, the pile rig couldn't reach that height, then they also encountered some boulders that made it impossible to drill the piles. Quite interesting to work alongside the engineer trying to solve the situation.
Twelve year old me could definitely not have watched this most informative videos on shafts, drilling, piles and shafts.
Always interesting and educational. I love this channel.
I remember a railroad grade separation project in the 1970s or 80s where sheet piling was used. It took much longer than expected to install the piling because the soil had been compacted from trains including steam engines going over that ground many times each day for many decades. The sound of the pile driver could be heard all over town for weeks.