Why Are I-Beams Shaped Like An I?

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[@RealEngineering]

Hey Guys. I just pressed publish on this video in a pitch to the judges of the Best Young Irish Entrepreneur awards. Was so nervous, yall notification squad people did me proud. 1000 views in the 10 minutes I was talking and they could see it coming though on my live analytics. Ye are the best! As always, ask any questions here or on my twitter. twitter.com/fiosracht

[@JanSenCheng]

That's great. You got a thousand more since then. Hope you manage to win that award. :)

[@Brett-kg7je]

Real Engineering Congrats man!

[@DesNorman]

Wish you all the best man your videos are top class!

[@FreedominThought]

another good video and good luck on the award!

[@RealEngineering]

Didn't win! The winners had fantastic businesses. Medical devices, apps to help the elderly track their medication and research referencing software. A KZbin channel with zero employees was never gonna win it. Was nice to be involved though and made some great connections!

[@ChrisKogos]

Because they're called I-Beams

[@tycoongamer2416]

😂😂😂😂😂

[@puspamadak]

Lol

[@ImranZakhaev9]

They're really called W-sections, or wide-flange sections. (Unless they're a weird type like S or M)

[@Twiggy163]

But... Its more like an H (on its side).

[@user-du1rl3hj7f]

Honey

[@RealEngineering]

There is a type in that equation, It should read L^4. Thanks to everyone for pointing it out. That's what I get for rushing a video and not proof reading!

[@afswan]

*typo

[@alienmechanic8696]

how about square tubing?

[@rjfaber1991]

+Alien Mechanic - The same principle, but applied along both axes, so it can withstand both horizontal and vertical forces as well as possible, with the minimum amount of material.

[@RealEngineering]

God damn it 😂

[@alienmechanic8696]

I was wondering because the i beam is symmetrical where the center peace is connected to the top and bottom peace with a radius on both sides, a square tube is not symmetrical, it have a different radius on the inside of the corner than it has on the outside of the corner

[@xennelul]

I like how you explained in less than 4 minutes a whole semester of engineering.

[@gWMPH-qi3nk]

Yeah, Mechanics of Materials was a nightmare.

[@ebubechioti7410]

1.21gW &88MPH in my case aircraftstructures.

[@hurrdurr3615]

Well that was an easy semester

[@prelude12341]

not quite.

[@squeakybunny2776]

You did a whole semester on one equation.....? Where do I sign up?

[@TitanFlare]

I learn more from your videos than I do from my engineering school. Like really, learning the calculations on my own is good, but these videos help to see things conceptually that you can’t possibly see from a textbook. Thanks so much for making these!

[@TheRoadsHereSuck]

Because if it was shaped like an L, the name "I-beam" would be misleading.

[@alenngk]

You can use L beams too, they are cheaper to made but resist less tension. You can use them for bender force more than pressure force. Best shape is closed beam like rectangle, they resist in two direction in contrast to I beam that is prone to sideslip.

[@ENGR-od7ft]

L shape beams are more used as Girts or braces. And when you say closed, you probably mean hallow, like HSS's (Hallow shaft steel). If you're an engineer please use appropriate terms.

[@rutvikdangarwala9496]

@@ENGR-od7ft This is when one gets into too much technicality , Misses the joke Same with life ;-)

[@annonymouslibertairian9120]

@@alenngk you mean un-equal angle?

[@_bee_1088]

@@alenngk and i always thought that best beams are pipes))

[@MeanGreenLuigi]

I wish my construction professor was THIS informative and down to the point with their lectures like you. I look forward to your future videos.

[@263kiki]

watching your videos while being a mechanical engineering student is really a joy, keep up the dope work

[@jerome1lm]

#metoo ;)

[@konstantinos.varva1]

did you finish ?

[@TheWeilor]

i strongly prefer longer video format. I love your videos, keep it coming !!

[@RealEngineering]

Me too, I am already working on the next video. This was part of that video, but it felt a bit tacked on at the end, so I decided to split it into two. The next one will be a solid 10 minutes long alone.

[@thethyphoon6370]

long videos give you a more complex way to explain things and can add some minuscle details but this format will also make viewers bored and wont end up watchign the whole video and a short videos makes you to compress the size of the info you want to give, I strongly suggest you try to make a video where yourself feel comfortable in giving all the info you want while trying to hold it short but not to short. PS: Cheers on this vids

[@judgeholden6761]

One of my favorite examples and the earliest I know of personally is the sword. A fuller (or groove) runs down the center of the blade on either side starting in at least the early dark ages in Europe making the weapon lighter but still strong, with a cross section resembling an I beam.

[@mihailmilev9909]

This is exactly what I thought as well and what I came back to this video for. But if you think about it he said the I beam is meant to resist bending parallel to the long part of the I, if that makes sense. Same thing maybe goes for a fuller on a sword. Which is very important for it not to break or bend, but also what is important for edge alignment is minimizing bending along the axis perpendicular to the length of the blade. Which is what usually occurs with spring steel although it is still used and considered better because flexing is way better than breaking. And I just realized that this is why Katanas and blades with thicker backs are stiffer, because they just have more material in that bending direction, which is basicaly just what an I beam does, maximizing the amount of material in the reigions with the most stress during that bend.

[@mihailmilev9909]

Also how's the last 5 years been lol

[@scott8074]

Because the letter H was busy.

[@arthas640]

The letter "H" is one of the least sexy letters, along with "Q" and the umlaut. "X" and "V" on the other hand are extremely sexy. Check my Tumblr page for my complete list of "every letter in every alphabet for ever language ranked by sexiness".

[@theomnipresent1]

You actually made a list?

[@NoNameAtAll2]

+Arthas Menethil You don't have enough imagination H is a "right before *it* is inside" pose h is pretty obvious, on the left is the man, on the right is the woman Q is top view of man q is 69, but 1 partner leaks feet of another

[@MrPRECLIK]

No, H beam,U beam an L beam exist too

[@ChrisWongHiro]

There are actually "H" shapes. But they are used as steel piles that get rammed into the ground.

[@larrywestenberg7839]

A deep bow of respect. I write training for a living. Somewhere in the field of Education, they decided you must ramble incessantly in order to teach things. I work in Fortune 50 companies, and they assume every employee is as ignorant as a 1st grader. This means training is boring as HELL for everybody except the completely ignorant. YOU just taught a HUGE bunch of fantastic and well-related information in a clear, STRUCTURED, visually supported training. THANK YOU for being a wonderfully efficient teacher, and saving me from the history of I-beams, the best materials for I-beams... blah blah... NICE!

[@vincentmereeksson736]

Already knew but cant stay away from these videos haha!

[@TheLTcousins]

Studied strenght of materials in university for a year and i never tought about these questions or solution.Great video!

[@DanHowardMtl]

I want to know why the I-beam is used as the mouse cursor for text.

[@XmarkedSpot]

It certainly indicates both horizontal location and the height of the line.

[@iAmTheSquidThing]

Same reason. A thicker cursor would be heavy and sluggish. But a straight line would risk buckling under heavier font weights.

[@MRoesterreicher1]

:D!!

[@alexwang982]

why is the x beam the mouse cursor for dragging windows

[@sean.durham999]

3.14159265358979323846264338327950288419 I don't want any damn cake! I want me some pie. LOL

[@unrealed]

I don't want a shorter format, like this one. What I love about your channel is how you go in-depth on a subject, and explain it really clearly. This one was in-depth but maybe less clear than usual and than I would like. I do understand that there's realities of running a KZbin channel though, and if that's how you can make money then go ahead, this video was still pretty great.

[@DrathVader]

I-Beam sound like something Apple would made. iBeam.

[@iz723]

An overpriced laser pointer

[@arthas640]

If you take an I-beam, spray paint it chrome, and slap an Apple logo on it, you can charge ten times as much and people will still buy it even when it folds like paper #bendgate

[@JAnx01]

Apple should sue the I-beam.

[@a.nameline653]

Shhh! Don't give away your iDea without a patent and Non-Disclosure Agreement.

[@patrick_test123]

You could also call it a double T beam.

[@wierd657]

Good 2nd moment of area demo is in studs and joints in a house where wood above doorways, in the roof, and in the subfloor is on edge to maximize the 2nd moment of area. Also in wood, demo the effects of horizonal shear and how the wood splits along the grain.

[@SirWrender]

Great video, Brian! I really liked this one.

[@RealEngineering]

wrenthereaper Thanks! The 3D I-beam looks so janky, but it was a good learning experience. Do you have any recommendations on software for 3D animation?

[@SirWrender]

Real Engineering Element 3D is a fantastic starting point for learning that sort of thing if you haven't gotten it yet. It's pretty powerful too. For the I-beam you could make a mask outlining the cross section and then extrude it. Element could then distort, twist, and bend it which is cool.

[@RealEngineering]

Yeah for this I just built it from 2D pieces in after effects. Not exactly efficient. Will check that out

[@jeruelnathan1845]

If u dive a bit deeper it’s found that the web of the I beam mostly carries the shear force and the Flanges carry the bending moment making it greatly efficient! Great video mate!

[@emcd173]

An example in biology would be the tensile strength of microtubules - which are hollow cylinders made from a repeating protein structure. With all the mass on the outside, they have very long persistence lengths and are far stronger than other cellular fibers.

[@ivangalik7848]

for tension you dont need any inertia only area

[@stepandanek6138]

I went to school in the field of architecture and reconstruction, but lessons of construction and static mechanics are still mandatory (I'm translating from my language so this might not be exactly how they're called in English). You explained the properties better than any of my teachers, and even though I already knew how the I beam works, it was still helpful as a reminder.

[@abyssaljam441]

Can you do a video on the engineers general formula (M/I= σ/y=E/R)?

[@d3x-dt3]

Abyssaljam great idea!

[@livethefuture2492]

pi=e=3

[@tycoongamer2416]

@@livethefuture2492 g= 10

[@walterwhite28]

Read Strength of Materials from the book SS Rattan. It has derivation of those formulae. It is a standard engineering book recommended in India.

[@arjan5071]

Me: Sees formula Mechanik exam flashbacks

[@ulyssesmoura4890]

Very good explanation! I explain using the inercia momentum formula: I = (b*h^3)/12, this formula represents only the geometrics propreties of the structure, and how only changing the "h" value contribue to Inercia much more than "b". The deflection formula i use to explain the combination of material and geometrics (E*I ) do the resistence against the solicitations (w, P, M)

[@maskedmonkey2]

Hi! Great, simple explanation. One pedantic note though, The profile you have drawn there is not an I beam, it is known as a wide flange or W beam. True I beams have tapered flanges.

[@scottvincent1262]

maskedmonkey2 I’m afraid not, that would be a rolled steel joist (RSJ). At least in the UK and Ireland.

[@weezyalmon8100]

scott vincent Ask any practicing Structural Engineer. He is correct.

[@kylomeg]

We were literally just discussing why I-beams were so efficient in my lecture this morning. So weird that you decided to release this video at the same time! Really interesting though, good to see it explained in a little more detail!

[@manunen00]

You don't get enough love I am obsessed with sciences channels good job

[@jynestaugustine6497]

yeah, me too

[@jaredraynor9067]

Here in the US, in many smaller scale residential and commercial building applications we have transitioned to i-joist made out of recycled strands and veneers of lumber. They can vastly out perform traditional dimensional lumber, in span and resistance to deflection.

[@SirChocula]

There's also an "I" in illuminati... coincidence? I think not! Wake up America!!! - cue x-file music -

[@Brett-kg7je]

SirChocula IT'S A CONSPIRACY!

[@kwestionariusz1]

There is an I in idiot like you can see its conincidence in it ;)

[@SirChocula]

kwestionariusz1 grammar so bad even the nazis got cancer from it...

[@swaybelly3212]

Irony...

[@elliotlea5457]

Don't you mean IRON-E?

[@ezla1663]

Pretty cool! Used it for building popsicle stick bridges. The I beam provides a lot of strength!

[@DerpyPenguin4747]

"These equations arent complex" *head explodes*

[@Kyrinson]

Thanks for the video! It very nicely summarizes why I-beams are shaped like they are in words that non engineers can understand.

[@johnossendorf9979]

Real Engineering: Cold you do a video on the difference between an I-beam and an H-beam.

[@ianbelletti6241]

the height may be for load but the top and bottom plates prevent twisting of the beam under load. You can test this with strips of sheet metal. A flat sheet will easily twist but putting a bend lengthwise through the material causes it to resist twisting. The reason for the I-beam's shape them isn't just minimal material for the load because that would be a flat plate but minimal material while preventing the twisting of the support.

[@KingManuBoss]

I like the longer videos more

[@asdfghjkl7895236]

In India, this is a common interview question in engineering professions. Thanks for a real visual interpretation

[@jiriatanasov7479]

Only bad thing on these beams is that they can be easily melted by jet fuel xd

[@Alvy.07]

Jiří Atanasov I see what you did there.

[@AnixCo1990]

I beams weren't used in the construction of the wtc it was trusses. Had they been used the towers would've stood much longer since trusses lost their strength faster in a fire because they were lightweight in contrast to I beams.

[@sultanabran1]

so much ignorance in this line of comments

[@billhamilton2366]

And forests burn ...what's your point other than a stupid comment about 3000 people being murdered

[@mr.boomguy]

Jiří Atanasov - And that's what happened with 9/11 guys!

[@klausm5460]

Bones are also built that way. In a long bone like the femur the strong bone material is distributed as a tube around the soft bone marrow. The bone marrow is protected inside where it does not have to contribute to bending resistance in the neutral axis. Near the joints where shear stress is abundant that principle is supplemented by a frame of thin bones that work as struts to distribute the forces.

[@25NN25]

its called 'double-T-Beam' in german ;)

[@louis-philippelavoie6929]

And W is pronouced V ...those germans

[@jerome1lm]

Not according to my professor. But in everyday language yes.

[@stephen-toth]

BTW I use arch

[@emilgabor88]

Louis-Philippe Lavoie And V is pronounced F

[@VitaliyHTC]

Huh, the same in Ukraine or Russia. Double T beam

[@adirocks009]

dude I love your videos... please don't stop...wish your channel all the very best... KZbin needs more people like you...

[@Freddan0]

isnt it supposed to be 5wl^4/384EI and not L^3

[@carultch]

It depends on what w stands for, in your application. If W (usually capital) means total uniform load, then it is L^3. If w (usually lowercase) means uniform load per unit length, then it is L^4.

[@comptegoogle511]

The ''I'' shape is made to increase the flexural stiffness and load resitance in the longitudinal direction while using a minimum amount of material by optimising the beam's moment of inertia of the section by applying the parallel axes principale.

[@CaptainWicket]

Wait a minute... our bones! So many of them (femur, tibia...) have that I shape!

[@RealEngineering]

Samnang Eang bones internal structure is very complex. I'll be doing a whole series on the engineering in the human body some day

[@CaptainWicket]

Looking forward to them!

[@l1nkd1]

Real Engineering You are right living organism is more complicated. But the answer is more simple. These bones are constantly under axial compression and not under a bending moment ( at least not normally). More like a column than a beam. Now buckling is another topic. Cheers

[@arthas640]

Does anyone actually still use that shape for a capital "I" anymore? I dont

[@louf7178]

Arthas Menethil Yes, clarity is important.

[@VipulAtri]

1:14. I think you wanted to say: If weight is placed in the middle it actually very difficult to lift, but at the ends it is easier to lift due to leverage.

[@CatNolara]

Make a video about why C- and U-profiles aren't that good compared to closed tube profiles.

[@prelude12341]

because they're unstable. the flanges tend to buckle under axial load.

[@williamhoughton2140]

It is called an I beam because of its shape , the middle vertical part is what carries the weight, the flat parts ,top and bottom are used to hold it up from underneath, in the open area , the upper part to hold bricks for the wall above. This is a very stable method, vertical and horizontal movement contained. This is cost effective, saving weight , but giving maximum strength.

[@lefr33man]

because O-beam isn't as catchy.

[@drink15]

Because we just call them pipes.

[@lefr33man]

drink15 :O I have been enlightened. From now on, I will call pipes "O-beams" !

[@arthas640]

No, it's because it's harder for the electricians to attach their conduit to an O-beam than an I-beam. Electricians run the show B-)

[@user-ky6vw5up9m]

O beam is called “round hollow section” and strength comes from the wall thickness to diameter ratio

[@TannerForrest]

Anyone remember O-Game? No? Just me? I need to go collect more deterium now..

[@mgs771]

we use it to make our lorry bodys etc not only for how strong it is but because it can twist and flex, stopping the welds from cracking witch is a must!!

[@TheNicolaivlog]

Nice vid! I like your longer format better :)

[@ProtonChicken]

We are building balsa wood bridges in AP Physics C currently and this video is definately going to give my partner and I a huge leg up. Amazing video, so glad I found your channel.

[@Ethan_Roberts]

Because if they were the shape of a H, they would be H-beams.

[@Dav2Kink]

Which is another type of steel rolled shape also made

[@ronjohnson303]

If you lay it on it's side it's an H beam

[@jusufagung]

Actually ..... it's an H instead of an I .....

[@walterwhite28]

You can't load an H-beam. The stress concentration at intersection of flanges and web would be too high.

[@383mazda]

Brings my back to my civil engineering 101 class. The idea is to get as much mass as far away as possible from the neutral axis in order to resist bending - thus the battle between engineers who want 5ft tall I beams and architects who want 5 inches, lol. "H" and "I" beam connecting rods are another good example of this design.

[@HackersSun]

(gives you dirty look) *_SEAR'S_* tower

[@Strideo1]

Yes!

[@harrisashraff]

I studied civil engineer and this is the first time i am seeing someone explaining the moment of inertia precisely... thank you real engineering..

[@jaimemunoz5920]

Is it an I beam or an H girder?

[@The1Helleri]

There is another side to it as well. That shape is a lot easier to work with then a solid block. You can maximize space for storage and transport. They are easier for mechanical hooks, claws, chains, and safeties to find purchase on. And because they are pretty much the same thickness at any given surface you don't have to mess around with nearly as many lengths and diameters of of bits and rivets. There are probably other configurations in cross-section that would work just as well for strength concerns. But not also for ease of use.

[@benboys_]

then why isnt the middle bit micron thin?

[@RealEngineering]

It still needs to resist sheer stress. We want to minimise that section (called the web), but there are other forms of stress it needs to resist.

[@lebagelboy]

Also if you make the web too thin it can fail through buckling. This is a common failure mode when using light gauge steel (1-2mm thick). (You can get round this issue to some extent using stiffening elements)

[@benboys_]

thats the shear stress though, right? so your saying the same thing as realengineering

[@damien4197]

Why not make it thinner then, but in a wave down the middle? Or is that just too hard to produce reliably? Also, I had a different answer in mind when I saw the video title... in that when you try to bend something with a T shape you're actually effectively trying to pull the crosspart to the part you'd bending apart end to end (tension, yes?)... which is, comparatively difficult? Does that play a part here?

[@carultch]

@@damien4197 With rolled steel sheet metal purlins, they do build the structural members with waves along the middle for improved strength. This is thin sheet metal that is 1/16" to 1/8" thick max, and it is cold-rolled to its shape. With the I-beam and wide flange beam, the inner part is hot-rolled from a red-hot solid rectangle of steel. It is too difficult to reliably produce waves in the web, and there wouldn't be any significant benefit to it. What we've got already works, and the web is thinner than the flange. A beam flange might be a half inch thick, while the web is less than a quarter inch thick.

[@wafflyhawk]

Another example of its effect: Its a lot harder to bend a hollow cylinder vs a solid cylinder made out of the same amount of cross sectional area. It's so counter-intuitive because there is literally a hole in it! When I learnt this I didn't believe it, so my engineering teacher made copper ones for us to bend by hand.

[@tjrsasea]

Isnt it simple? If its not shaped like an "I" it wouldn't be called an I beam

[@iant720]

tjrsasea Could be an H beam ;)

[@jaykoerner]

tjrsasea what would a lower case i beam be called?

[@kiefac]

Jay Koerner maglev beam, how else would you get the dot of the i

[@user-nx8tk1pp5o]

Don't forget to mention that the highest shear is at the neutral axis.

[@SpektralJo]

Easy, else we woulndt call the I-Beams :3

[@jordr94]

Another interesting place you will find a similar design principle is shipping containers. Sides of the shipping container are corrugated in such a way to increase 'I' along the shortest side, increasing the overall stiffness of the structure.

[@nyx9208]

answer: its not its an H sideways

[@gregwarner3753]

Please consider the sheer stress along the web of the beam. Another example is tube type structures ranging from an ancient railroad bridge in England to all the unibody cars, boats and frameless aircraft. All of these carry the stress as far away from the center as possible.

[@1pcfred]

I beams sort of went out of style about 100 years ago. We use H beams now.

[@ragnkja]

Same general shape, isn't it?

[@1pcfred]

Nillie I beams and H beams are about a similar as rectangles and squares are. Which is to say vaguely, but they're different. I beams are taller, and skinnier in cross section than H beams. Though people that don't know call H beams I beams. Which is most everyone.

[@ragnkja]

Paul Frederick So the middle beam is shorter in an H beam? That's what I'd imagine the difference would be, at least.

[@1pcfred]

Nillie The parallel sections are longer. They probably lacked the tech long ago to draw metal so far. I beams were easier for them to make.

[@ragnkja]

Paul Frederick If the parallel sections are longer relative to the middle section, then the middle section is shorter. ;)

[@thesnowyacht3753]

Wide flange beam: looks like a capital H over its cross section. The H-beam has wider flanges than an I-beam, but the I-beam has tapered edges. The width is the flange, and the height is the Web. The difference between both H-beams and I-beams is the flange by web ratio.

[@caifora837]

JET FUEL CAN"T MELT STELL BEAMS! Kappa

[@NicklausSIR2]

That is the main reason, but I think to get the complete answer, you'd need to talk about the cold rolling techniques that allow this shape to be produced massively. A square or round tube essentially does the same thing, but in several directions and that makes it also better for torsion resistance. But these shapes are more diffcult to manufacture and also to assemble.

[@FivePointsVids]

The important question is WHY ARE THEY CALLED I BEAMS??? Answer that mr. smarty man!

[@Kuldeepb14]

In this equation we can play with only WITH Inertia rest can't be changed because stiffness material are unchanged . This is why Holllow cylinder takes more load than Solid cylinder . Because mid along any larger axis , only outter fibre takes load( Tau And sigma) in case of complex load ,not in pure shear and bending

[@MidnightMechanic]

Now to calculate if jet fuel burns hot enough to melt them...

[@carultch]

Jet fuel cannot melt steel beams. However, raising a beam that hot from jet fuel, can seriously weaken steel beams, to the point where they are completely useless as beams. Yet still solid enough that you can hit them with a hammer and hear it "clang".

[@NiteSaiya]

They taught this in my Sophomore Statics class at uni. First real engineering class. the entire last month of the course was sheer and bending moments, center mass, and this sort of thing.

[@paulorschmitt]

Most of the largest vehicles have their chassi made of C beams that uses the same Inertia principal, but are much more easy to build and assemble with the rest of the vehicle.

[@MRoesterreicher1]

very nice simple explanation! however I would not only stress on the bending deflection, but the bending Stress itself, simply because beams are usually dimensioned(or selected in norms) by stress; Examples where they are dimensioned by deflection include machine tools : lathes,mills, etc... (precision is needed) Bending stress = (Bending Moment/Second Moment of Area )* max distance from neutral axis to the end of material

[@altantic905]

You can also take, sigma= WL³/(4bd³Y) where, sigma= depression/buckling , w= work done L= length of the beam, b= width d= it's depth and Y= Young's modulus. I think it's an easier way...btw I'm from class 11😁

[@user-yv3ro1fo7w]

This concept is also the same reason that swords have grooves running down the center. And if you look at some of the later patters in hardened/soft steel in Japanese sword smithing you can see similar tactics being used. Love this channel and continue to be surprised by the amount of work that is put in to planning every detail of modern construction. - любовь из Америка.

[@Raptor05121]

Aircraft wing spars are I-beam shaped aluminum, with lightening holes in the middle

[@cmr2153]

I like seeing this as i am currently learning that in my studies for civil engineering.

[@KoalaKrisp1]

same!

[@KoalaKrisp1]

What uni?

[@machia-mw1lm]

Compression Bending Tensile Torsion Shear

[@cmr2153]

KoalaKrisp1 Koblenz (dual system so basically apprenticeship and studies in one)

[@AS-fm5ew]

I am becoming addicted to this wonderful channel. Thanks a lot for making these videos.

[@fakjbf3129]

I always figured the middle portion would resist vertical stresses but be weak to horizontal stresses and the top and bottom would be the reverse, and so overall the shape would be relatively strong in all directions while minimizing materials.

[@ytrabbithole6893]

This is unrelated to moments of inertia, but perhaps a good video idea would be how the cone shockwave on the SR-71 blackbird was used to slow air down to subsonic speeds before entering the turbo jet. Ever since I started learning about that plane and the engineering behind it I have been fascinated. P.S I am studying mechanical engineering and I thoroughly enjoy your videos, keep up the good work!

[@johno9507]

I beams are also used for wing spars and keel beams in aircraft.

[@userou-ig1ze]

I'm a fan of your original length or videos- it seems authentic, interesting and concise. This is too short(not informative enough) and others were too long(not interesting/catchy enough). Please do more of your original ones!

[@Franstocco]

I Think you could talk about the resistance of a column, in fact the more moment of inercia, the more the column resist to compression forces. thats why the columns sometimes are empty, because the iner part doesnt helps to resist weight as not much as the parts on the edge

[@carultch]

When it's a short column, that ultimately doesn't matter, since direct compressive yield/rupture would be the failure mode. When it is a column of significant length, shape does matter, because buckling failure (elastic instability) matters more than direct compressive stress.

[@yoshyoka]

Truss structures are a gorgeous example.

[@LT72884]

a couple of extra tidbits. Back in the early days of the industrial revolution, beams were actually rectangular. Then when this was discovered, they were able to save tons of material and money on beams and structures requiring these beams. Another way to look at it; take a yard stick, grab it in both hands, and flex it it. Notice how when the yard stick is flat, it flexes like crazy, VS the other direction. thats because the same principle applies to the neutral axis. Sources: My strengths of materials text book

[@curicastevic]

When I'm riding the bus, I can't help but think about this every time: The further your feet are apart - smaller amount of braking/moving force affects you. This is of course if you're standing perpendicular to the driving direction, whereas if you're facing the driving direction, you have much smaller moment of inertia and are much more prone to wobbling around.

[@mattberg6785]

Another application of this theory is reinforced concrete. The steel bars are placed as near as possible to the top and bottom of beams to create top and bottom chords

[@currotrololo]

When you are eating pizza and the end of the slide in folding down letting all the food fall in the ground but you can solve it increasing the moment of area by folding the pizza around a horizontal axis

[@craxd1]

Instead of looking at the section as a beam, look at the section as a column. The web is strong enough to stop deflection/buckling in one axis, but not the other. The two flanges stiffen it in the opposite axis. Thus, you have a light column that will support the load and not buckle in both axes.

[@johnbarron4265]

A rectangular tube is far better as a column than an I-beam. I-beams are only for supporting transverse loads.

[@wesleyarnold9269]

Is ANYONE else triggered that an Engineering channel isn't calling this a "W Section" ... which is what it actually is : - | Also you need to specify during your application of downward force example if it is being applied at the end of a W section or the middle because if it is at the end, then the top is in Tension and the Bottom is in compression. Shame Shame Shame .... also, I like your channel ;-)

[@harleycurnow5242]

Why is it called a W section? I've always known it as an I beam or RSJ

[@RealEngineering]

I, H, W and RSJ are all essentially the same thing.

[@wesleyarnold9269]

W is for "Wide Flange" beam

[@wesleyarnold9269]

While essentially true, I just though you would differentiate them since all differ based on location of tapering / presence of tapering and flange / web ratio.

[@Andreycs0]

"An I-beam, also known as H-beam, W-beam (for "wide flange"), Universal Beam (UB), Rolled Steel Joist (RSJ), or double-T (especially in Polish, Bulgarian, Spanish, Italian and German), is a beam with an I or H-shaped cross-section."

[@Cannibal713]

I just discovered your channel and have been pouring thru them. Great stuff bro. Very informative and interesting. Good job and keep em coming. Thanks.

[@Johny40Se7en]

"I watched C beams glitter in the darkness at Tannhauser gate" =P Good stuff

[@boffinboy100]

Amazing timing posting this - I need to (in a group) design internal structures of a wing for our uni UAV project and your video just gave a good reason to try I beams, especially as weight is a premium...

[@EatEaty]

You'd never carry a mirror around with the wide side horizontal because it would break under the great bending. Carrying with the wide side vertically there is merely any bending for the same reasons.

[@PortCharmers]

So a typical crane (or Zeppelin) girder would be this principle taken to the extreme? Place the material where it is compressed or under tension, and leave just enough of the rest to hold it all together.

[@dj394]

Wow, very well explained! I am in my senior year majoring in civil engineering and I did not know this.

[@NachozModz]

This could've also been explained through maximum shear at the edges of an object as it has max stress there as well. Therefore, the more material on the edges, the greater the resistance to shear and therefore less stress. But yes, most obvious way is through second moment of inertia.

[@abcmichale]

Well, if I remembered it correctly then Sydney harbour bridge uses some super long curved I beam, and its two "horizontal" part are connected with bolts to the vertical part.