I got to work in one of testing labs at NIST (fixing the elevator). They were testing highway support pillars for earthquake designs. They also were testing a keel design for supertankers. Watching a 30' x 8' round concrete pilar twisted and shaken till it failed was very interesting. The keel test was not as dramatic. Made me appreciate all the talent that engineers and architects bring to our everyday lives.
@FalconPunch19787 жыл бұрын
Everyone in the comments apparently works for osha..
@BryanTorok3 жыл бұрын
I'm impressed that the beam failed in a controlled manner and never actually completely fell down. If this had been in an actual bridge, the cracks and deflection would likely have been noted and the bridge closed long before there would have been loss of life. Even at the end with massive deflection, the bridge would still not have fallen.
@jeremyvallier3033 жыл бұрын
Maybe, but you have to remember that the load press is designed to stop applying load once a certain yield is reached. so at final failure, the load was removed. In a real application the load would have continued to be applied, until free fall of the bridge.
@romeoETmike3 жыл бұрын
It's a controlled pressure. When the samples break, the hydraulic machine stops.
@docfarl8 ай бұрын
It was purposely designed as an under-reinforced or balanced design beam. Which means the steel tension reinforcement yields first (and slowly), before the concrete in compression. If it had been over-reinforced, the concrete would have yielded explosively before the steel reinforcement and should be avoided for obviously reasons.
@boldger1310 жыл бұрын
First crack @ 2:00 Close up of 5 large cracks @ 3:35 Major deflection and ultimate failure @ 4:57 Major deflection and ultimate failure up close @ 5:50 Best @ 6:13
@ronierjones7 жыл бұрын
Maxwell Goodacre o
@nigel9007 жыл бұрын
Yes... we saw.
@simoncheung25737 жыл бұрын
Ty
@JohnJacobJingleheimerSchmit7 жыл бұрын
Thanks
@wilkyahzee23357 жыл бұрын
Maxwell Goodacre Which is the best crack?
@kevin_19792 жыл бұрын
I'm amazed at the lack of safety glasses and people being so close.
@jerrymclellan47112 жыл бұрын
I kept waiting for it to break, and send a splinter through Blue Hat's forehead.
@slimjenkins97282 жыл бұрын
Fuck it
@parttimelaowai17712 жыл бұрын
don't you get it? these dudes live on the edge...
@popogast8 жыл бұрын
I like this procedure. When I studied some decades ago, we students were given the task to estimate the load when first cracks appear, the deflection at this load and the maximum load the beam would bear. We were given all the information of the continuous rectangular cross section, reinforcement and cube strength and E-module of the concrete. We also had 2 point loads. 4 weeks after casting we could watch the experiment like the one shown. It was very illustrative as we found out, that the formulae worked very good.
@richavic45207 жыл бұрын
popogast who won the pot?
@TC-zi2yp3 жыл бұрын
Ladies and gentlemen, a round of applause for the hydraulic press operator!
@next08453 жыл бұрын
I initially thought it was a steel beam until it shattered
@jessequentin44413 жыл бұрын
same here haha
@DanFrederiksen6 жыл бұрын
The bridge that collapsed in florida had stress cracks on its underside and it was reported by an employee 2 days before the fall.
@davidhelsem87943 жыл бұрын
Two days is not long enough for a bureaucracy to get moving. I am sorry, it probably cost lives.
@davidhenderson34003 жыл бұрын
66 KN is 14,877 pounds 156 KN is 36,070 pounds 163 KN is 36,644 pounds if anyone was wondering.
@Kalumbatsch3 жыл бұрын
Yeah, that's helpful for anyone still using neanderthal units.
@arcadecarpet6313 жыл бұрын
@@Kalumbatsch like me
@HitLeftistsWithHammers3 жыл бұрын
Wait, did you put an extra 3 in there by mistake in the last one or am I stoned? Not mathing well right now 🤣
@HitLeftistsWithHammers3 жыл бұрын
Also I i think it is 18.3 tons if anyone is interested and doesn't want to type on a search bar 🤣 Again I may be wrong and just being dumb as shit 😂
@Chief_53 жыл бұрын
I was wondering 💭
@zbeshears69453 жыл бұрын
Hey I worked for coreslab Structers for almost 7 years! It was amazing the stuff we got to erect that came from the yards that were made of concrete.
@mentaldetectingireland3 жыл бұрын
Pressure from the mother in law.slow at first and then the cracks in the paint start to show.never ending pressure until collapse.
@WELLINGTON203 жыл бұрын
Well it isn’t painted so your incorrect.
@tomassinopatatov1353 жыл бұрын
aha, no safety screens
@godbluffvdgg3 жыл бұрын
Wow, as strong as 163 Fig Newtons! Man, that's a lot!
@robertpendzick92503 жыл бұрын
Did this beam 'win' because it was most cost efficient, held the most, lived up to the predictions best, easy formation, some weighted combination? Explosive failure wonder whey there is no shielding?
@Rahul-ey1oq6 жыл бұрын
Why no personal protection equipment?
@nickwustrack91323 жыл бұрын
They had helmet.
@antpoo3 жыл бұрын
So even after it cracked and failed at 66kn, it still supported over 150kn and even with many cracks it stilled held strong. Until at least 163kn
@SAIGUK3 жыл бұрын
Its normal thing for reinforced concrete. There is no fail at 66kN. Concrete cracks because it can't handle tension, but rebars can handle tension.
@nairdacharles94923 жыл бұрын
@@SAIGUK More accurately, because it lacks the elasticity of the steel rebar.
@SAIGUK3 жыл бұрын
@@nairdacharles9492 Can't agree. Concrete has elastic modulus for tension and compression. Elastic modulus is nonlinear. But concrete cracks only because of lower ultimate tensile strength.
@denali94492 жыл бұрын
Spent two years of my engineering internship at the Portland Cement Association Structural Research Lab, the reinforced concrete equivalent of the PCI. While we designed, constructed and tested all manner of bridges and buildings I think my favorite was developing a reinforced concrete railroad tie. The tie not only must resist the zillions of cycles of the wheel loads but freeze/thaw and high temp cycles, abrasion from the ballast, side loads absorbed on curves and braking load must be considered. And to think I took them for granted.
@Don.Challenger2 жыл бұрын
Plus, as I recall from my own destructive testing days, heavy hammering with one of dad's best by ten/eleven year old boys (later I may admit to penny testings on the rails).
@hugieflhr033 жыл бұрын
I’m no engineer but is it a good idea to be sitting next to the beam being tested?
@kordapyo6123 жыл бұрын
And one is walking around..
@kemphoss-47913 жыл бұрын
*no safety glasses
@thomasmcnally973 жыл бұрын
Eh no these lads are what you call invincible gobshites
@bahn5ee3 жыл бұрын
Yes , if you know what you doing.
@MrZoomZone3 жыл бұрын
@@bahn5ee but you dont know what you're not doing.
@rcdogmanduh44403 жыл бұрын
Thought that paint would never dry!
@droppoint4953 жыл бұрын
😑yep
@MaverickRenegade803 жыл бұрын
I have so many questions. What's in the beam? Steel rebar? Tensioned cables? CFRP? What's the concrete made from? Does it have additives? What's the criteria for the test? Looks super fun.
@teeanahera89492 жыл бұрын
Not sure, a square hollow though is extremely strong as to the way it transfer forces around and I only know that from randomly watching a KZbin vid yesterday that was explaining some inherent failure in I beams. Might be worth searching with those search terms. I wonder if it had tensioned steel cables within.
@BMSworldNZ3 жыл бұрын
Quite literally the slowest - yet most entertaining video I've seen this year.
@af91263 жыл бұрын
wow no safety shields on utm 🥵
@rigardt5483 жыл бұрын
Don't need safety shields for concrete, the moment the material gives.. The pressure is gone.
@felixcat93183 жыл бұрын
It's good to see critical, load bearing construction materials being subjected to such testing. Lives depend on the quality of these beams.
@laernulienlaernulienlaernu89532 жыл бұрын
I'd love this job, especially seeing all the different types of failures. I've seen ones on glass before and that was a smashing vid.
@chang.stanley Жыл бұрын
Is the monitor doing that to prevent burn in? It's wiggling up and down
@polla225610 ай бұрын
Well spotted, it might be. My OLED TV has something called pixel shift, what you see here might be that in action.
@Don.Challenger2 жыл бұрын
Naively, I had it in my head that in this type of testing all human structure in the test zone was removed to a far distance per civil engineering standards - foolish me. At 04:25, when "orange helmet/blue t-shirt man" pushes the cardstock? under the beam while under test to sample fallen material - quite interesting - can they forecast the inevitable destructive collapse that accurately?
@DreStyle2 жыл бұрын
It does not fall down or explode when it cracks trough. the load is released because it's a press and not an object on top ☺️
@ronblack78703 жыл бұрын
this is my alma mater although electrical eng. but you would have lectures in this building and from an upper floor there were large windows where you could look into the main lab. they were always testing something either concrete or large wire ropes as thick as your arm to failure. this was back in the early 80's so yah i'm old. i'm sure things have changed there in 40 years. at that time the contest i remember was a model bridge with a span something like 3 feet. and materials were mostly anything . the winner was the one with highest strength to weight ration. so most of the models were wood/ composite.
@81806343 жыл бұрын
That was a lot more deflection before failure than I was expecting for concrete. The steel must be really stretchy, relatively speaking.
@denali94492 жыл бұрын
This is pre-stressed concrete, not reinforced concrete. The beam has internal cables which have a designed load applied to them prior to casting the concrete. These cables have placed the surrounding concrete in a "super-compressive" state and are absorbing the tensile load at the bottom of the beam. A standard reinforced beam would have failed sooner and more dramatically.
@carpballet3 жыл бұрын
Where is the slo-mo section of the video?
@savagedabs85363 жыл бұрын
It's over six minutes of watching it fail and I'd say that's slow enough. 6:12 it is in slow motion and shows the break.
@herauthon3 жыл бұрын
engineer: i think i can improve this beam a bit.. beam: haha... that cracks me up..
@vancekangyishu6 жыл бұрын
This shows why u have to under reinforce your beam ... So that the rebar yields first and there is ductile failure
@YoureWrongImRightGetOverIt3 жыл бұрын
How did you know when the first crack formed? Can't see squat
@bursztyn103 жыл бұрын
I believe there was a rapid change in tension sensor reading.
@nukeengineer52143 жыл бұрын
And the crack formation happens are very high velocities
@BardCanning3 жыл бұрын
is the monitor randomly moving the image to prevent burn-in?
@Paginski3 жыл бұрын
yes exactly
@benjaminlavigne22723 жыл бұрын
5:50 beautiful how concrete cracking can close without leaving a trace
@nathan872 жыл бұрын
Almost certainly steel reinforcement springing back and pulling it back into place. Wood also does this, by the way - when it loses moisture horrible looking cracks start to appear, then when the moisture content goes back up it seals back up perfectly like they were never there.
@charleslessig25923 жыл бұрын
How are the end supports connected to the press? What sort of structure is in the floor?
@nukeengineer52143 жыл бұрын
The beams are supported on triangular shaped structure which looks like a book end. The support structures must be bolted to the floor, which is made of embedded beams and concrete. Yes the floor is probably 10-12 feet thick of reinforced concrete.
@theoffice58343 жыл бұрын
So was that a good test or a positive test or a result they were looking for because I feel that is 7 minutes of my life ill never getting back.....
@denali94492 жыл бұрын
If it makes you feel any better, this was a contest between engineering schools to find the best design for a certain set of parameters. We will never know if it was a success or not because we do not know the results of the other teams.
@AngryHybridApe3 жыл бұрын
Ship it before it gets too noticeable.
@rcdogmanduh44403 жыл бұрын
You mean paint it and ship it lol.
@77thTrombone2 жыл бұрын
I wished I'd've known about the Toronto Big Beam Contest during the COVID shutdown. I'd've sat for days watching the beam tourneys, 2014 through current, on the big screen in my living room.
@cyclemoto87442 жыл бұрын
lol
@cyclemoto87442 жыл бұрын
@@refuztosay9454 ?
@paddington16702 жыл бұрын
neeeeeeeeeerrrrrd
@peep393 жыл бұрын
Tons of force on something that will catastrophically fail, and sitting right next to it. Unbelievable
@gugleu93 жыл бұрын
And without safety shield or safety glasses.
@jamessouth47763 жыл бұрын
Ahh it's ok they went to university lol
@keep6cans3 жыл бұрын
Was thinking the same thing, the clap at the end is then all being like “yay we didn’t die on this one, next one boys”
@kimibaharev2 жыл бұрын
Why is the screen of the sitting guy moving a bit, like the dvd idle logo?
@69Xerosis2 жыл бұрын
i had to go re-watch.. but yeah that is kind nutty..? maybe something to do with refresh and the camera?
@billkillernic2 жыл бұрын
Probably a plasma or other technology that suffers froms burn in and has a technology to shift the pixels a bit in order to prevent burn in
@docfarl8 ай бұрын
My first concrete beam design project in college asked us to come up with an optimal profile, cross-section and steel reinforcement for a simply supported beam of specified span, to carry a specified load. I came up with a profile quite similar to the one being tested here ie. with a deeper cross-section at mid-span than at the ends. I was surprised however that most beams in practice (like those across highways) have the opposite profile, with deeper ends than at mid-span. Apparently, engineers in practice are more concerned with resisting shear forces at the ends than bending moments at mid-span.
@modefabrication15322 жыл бұрын
So they just sit around the beam with no safety equipment, no eye protection.:. But hats off to the whoever welded those damn carts!!
@Don.Challenger2 жыл бұрын
Episodic spalling shrapnel events are fairly uncommon beyond teacup saucer range, I expect.
@stevehuffman74533 жыл бұрын
I wonder what the failure would have been if the weight was applied evenly across the center, not across two 6 inch(?) 4 inch(?) wide areas a few feet apart.
@StagArmslower3 жыл бұрын
in real life the load is distributed on wider span, it's not the missile falling straight down; even truck standing on the road distributes the load between front and rear wheals
@HitLeftistsWithHammers3 жыл бұрын
Right. I understand that this tests an extreme, and I understand there is a point to that but some more realistic testing would be quite interesting to see, as would other extremes, like a full spread of the pressure application. I'd imagine a beam like this would be able to take a fair amount of crushing force before it just collapses. I wonder how these would do with say, 100 feet of earth on top of them, used as the ceiling of a bunker. Too many edibles tonight.
@casb24803 жыл бұрын
@@HitLeftistsWithHammers Actually there isn't much difference as far as the failure mode of this beam goes. The loading model for point loads vs linear loads is somewhat different but in the end it comes down to exeeding the compression capacity in the top or tension capacity in the bottom. That being said structures are always designed according the normative loads that are to be expected. (e.g. an column on a beam or floor could be represented as a point load wheras everyday use or snow is represented as a linear or areal load)
@elizabetholiviaclark3 жыл бұрын
@@casb2480 That's interesting to me. This isn't the same, but I'm reminded that the service strength testing of fire department ground ladders was accomplished by the application of point loads rather than distributed. My knowledge of that subject is quite dated, but here is a picture of current testing procedures, so it's done the same way now. www.ul.com/services/fire-department-ground-ladders-testing
@casb24803 жыл бұрын
@@elizabetholiviaclark also, for the sake of practicality; it’s far easier to do testing like this as opposed to applying linear loads
@SillieWous3 жыл бұрын
Yes, that looks like a safe environment to be in with 163kN loads until failure.
@presidentpotato2223 жыл бұрын
Same thoughts i am having ..sheesh
@samnass2 жыл бұрын
I guess they know that steel bends and concrete gets smashed with no flying objects...
@jasontaylor88778 жыл бұрын
Cool, during the fast forward bit you can see the burn-in protection on the TV slowly shifting the display.
@oBseSsIoNPC3 жыл бұрын
And I bet you would take even more load, if it wasn't for the tiny contact area of those 2 blocks with sharp corners biting into the concrete and really concentrating the load. I assume it is calculated to be there and in this manner. Impressive either way.
@droppoint4953 жыл бұрын
You know who else would take even more load?😏
@oBseSsIoNPC3 жыл бұрын
@@droppoint495 As your name suggests :D
@johncarroll86623 жыл бұрын
That would be a different test.
@muhammadrababa93202 жыл бұрын
hi im having my dissertation on flexural response of concrete beams reinforced with stainless steel bars at elevated temperatures...i need help!!
@poly_hexamethyl2 жыл бұрын
2:01 First crack occurs with 8.3mm deflection - that's quite a lot! Concrete is surprisingly flexible, that it could absorb that much deflection without cracking. Also, it's interesting that the deflection seems to be linear with respect to the load until the first cracks appear, after which it starts to shoulder off. What does that say about what's going on inside the beam as it bends?
@designstudio80132 жыл бұрын
the steel is flexible
@maxwang25373 жыл бұрын
Surprised to see the lack of care precautions for the risks to people around in a destructive load test like this!
@samnass2 жыл бұрын
It's safe...
@joewoodchuck38243 жыл бұрын
Why are we measuring in newtons all of a sudden instead of pounds or kilograms?
@melin19693 жыл бұрын
newton refers to force i believe ie the force needed to break the beam rather than weight
@joewoodchuck38243 жыл бұрын
@@melin1969 Ok, but why the change? I guess I have to look up the equivalent now.
@ddaytona13 жыл бұрын
@@joewoodchuck3824 Metric units are used as Standard in Engineering/R&D.
@Tinker19503 жыл бұрын
Two things about you are rather loud: 1. American 2. Not an engineer Not to worry though - you're in good company here I notice.
@joewoodchuck38243 жыл бұрын
@@ddaytona1 Kilogram is metric.
@ArsonistArborist7 жыл бұрын
Thats only like 35000 lbs of pressure, if I'm not mistaken? I thought a beam that thick would be able to handle a much more significant load. What kind of application is this beam designed for?
@jeffwilliams84647 жыл бұрын
D. Ryan Shaw i tried to look up what "kn" stood for before i commented and it was way beyond my ability of understanding. But i would think it was far greater than that?
@ArsonistArborist7 жыл бұрын
Jeff Williams I believe a kilonewton is around 220 lbs of force or so. My line of work requires equipment that is rated at 23kn's or greater and I'm pretty sure that's right around 5000lb's. So 1 kn would be about 220 lbs
@MegaJohnhammond3 жыл бұрын
the suspense is killing me
@douro206 жыл бұрын
What is the capacity of the machine?
@sless69283 жыл бұрын
Under that much stress it's possible something could fly off. Surely the operators would be safer in an elevated position and further away.
@conorfrancis2223 жыл бұрын
It’s concrete it just crumbles
@johncarroll86623 жыл бұрын
It was not their first beam. That day.
@romeoETmike3 жыл бұрын
it crumbles and much safer with the gradual force.
@32herz7 жыл бұрын
what's up with the computer screen image floating around when the video speeds up? some built in image burn prevention?
@shawnio6 жыл бұрын
literally no one is wearing safety glasses lol
@refusoagaino68246 жыл бұрын
I noticed that too. These boys are playing in the sandbox but they've not experienced the jobsite.
@graveyardrumblers6 жыл бұрын
That was neat seeing the way it flew apart at the top when it finally reached compression failure... Thanks for sharing.
@YabagVlog2 жыл бұрын
That's why It is ideal that the design of beam is tension controlled
@numair232 жыл бұрын
LEFM is a magical thing. When this video started I already knew where the cracks would form
@OzzieWozzieOriginal10 жыл бұрын
Questions guys, 1. for a prestressed beam, does it really need to have a bulge or deep cross section at the middle in order to have a higher bending moment capacity or load rating? Beam of this shape seems to have no beauty mah. 2. So when the strands broke, the beam went kaboom ? 3. In a real bridge, when a small crack is observed at the bottom of the beam, does it mean that the bridge should be condemned? 4. Vidcam you used in the test, how close to the test subject and what danger of being hit by the concrete pieces on explosive failure ?
@doylebros99 жыл бұрын
***** In any beam of any material, having a deep midsection like the one in this video will determine the overall strength and longevity of the beam. It seems like you might understand the concept of what I'm talking about, but think about a ruler standing on its side. You can bend it, but not much. Now add a second ruler standing the same way to increase the depth. It's nearly impossible to break when you try to bend. In terms of a crack in a beam/column on an actual bridge, only severe cracks will determine whether the bridge will need to be condemned. Small cracks could mean anything. As long as the bridge is under similar loading at all times, the crack should remain the same. If the bridge is in severe weather conditions, any crack is a problem. Cracks can be fixed fairly easily. Like any structure, maintenance needs to be done. As long as the student is standing a good 10 feet away, there won't be a problem. If your beam is exploding, then your construction is definitely questioned. I think a bolt failure on a steel beam could definitely cause damage to someone no matter how far away they stand.
@greatsea9 жыл бұрын
+Ozzie Wozzie Original -- you were reading my mind with these questions
@mikevolk44087 жыл бұрын
The deeper the belly on the concrete beam the stronger it will be since the neutral point will be able to shift deeper into the beam. concrete being ~ 12 times stronger in compression than tension. Not sure if that helps with your question.
@raybrensike427 жыл бұрын
This reminds me of how a steel rod is put into guitar necks, at a curve. Then it tightened to straighten out the neck, which would otherwise bend due to the tension of the guitar strings. When the curved rod is tightened, it wants to straighten, and this gives the "underside, if you will" a "lift". The greater the curve, the greater the lift.
@jeffwilliams84647 жыл бұрын
Ozzie Wozzie Original im not a smart man by any means but im assuming the purpose for tests like this is to put a structure under a much larger load then it would ever see under practical use, much in the same way osha tests safety equipment? Am i wrong? My question to you is do you think the beam would perform better if you filled it with self expanding foam or something to that nature?
@gregandmellissastephens1666 жыл бұрын
It's interesting the way the cracks are fairly evenly spaced across the beam. On in the middle, then one about eight inches on either side and then another about eight inches on either side of those. Is this a sign that the strength of the beam is very uniform across?
@emurphy81773 жыл бұрын
Bizarre lack of containment around this beam. Concrete failure of these beams during stressing is not unusual and can be explosive in nature with large pieces of concrete being expelled at high velocity. This is not a hypothetical safety issue. It's a real and extreme danger that any stresser will tell you about. For those of you questioning the lack of safety glasses and PPE. No amount of of PPE will save you from a baseball sized lump of concrete travelling at 100mph.
@shanesooth62673 жыл бұрын
I totally agree with you E Murphy I am a retired Ironworker and have experience stressing cables in parking structures and have seen blow outs a few times.
@carpballet3 жыл бұрын
Old dude in chair was chillin’. No biggie.
@romeoETmike3 жыл бұрын
Explode? Not in concrete that crumbles in a gradual force om a lab.
@shanesooth62673 жыл бұрын
@@romeoETmike those post tension cables can easily fling concrete pieces in a split second. I have seen it happen with my own eyes.
@paulkirkham8377 жыл бұрын
did that beam buckle at failure or was it the prestressed / destabilising load that cause that horizontal movement
@villacoya7 жыл бұрын
really? no one have safety glasses or any type of protection for flying objects.
@rotatingrecords7 жыл бұрын
first thing I thought too, they must not have OSHA in Canadialand.
@PlaywithJunk6 жыл бұрын
Did someone notice how the picture on the screen is moving around? Is this a camera issue or a screen feature like burn-in prevention?
@ozciva6 жыл бұрын
Play with Junk No. That is the substance you are using 🤣
@THOMASTHESAILOR7 жыл бұрын
We all love to watch stuff break.. It's important.
@epistte7 жыл бұрын
This is what engineers do when we are bored. Frack it'..................Lets go break something in the test lab!
@muhshekels53837 жыл бұрын
It teaches us the limits of materials. That's why nobody who has some experience with engineering and construction can, in the right mind, believe the official story of 911 and the collapse of the WTC buildings.
@JimmysTractor6 жыл бұрын
So, next time maybe a bit more concrete shifted to top center? Is there a link to what the limitations are. What about specifics on concrete for this bram? Fiber? psi designed and tested? Mix ratios? Just curious
@clinthymes59827 жыл бұрын
The beam failed under each point of force. I'd like to see this test and how it would react with one point of force in mid span.
@dphorgan7 жыл бұрын
Clint Hymes No fucking shit. What's with people's need on KZbin to point out the fucking obvious?
@domesday15357 жыл бұрын
as a matter of statistics the beam would yield at a higher force than in this test with a single point of force. These different tests are called three point and four point loading. The reason that four point loading gives a smaller number is because it tests a larger area of the beam for a fault which causes a large enough stress concentration. It can be counter intuitive but when it comes to ceramics like concrete two loads half the size are more likely to cause a failure than one load that's twice the size.
@Stephen28466 жыл бұрын
Like your need,..... and what you just did?
@MrZongee7 жыл бұрын
were they testing for unconfined buckling at the top?
@rrssmooth66433 жыл бұрын
looks like reinforcing did its job.
@DeyaShammar8 жыл бұрын
what machine used for this test ?
@drunkdonutboy8 жыл бұрын
You forgot to draw your free body diagram.
@Havazik8 жыл бұрын
Don't forget your shear and bending moment diagrams.
@arisz21917 жыл бұрын
Smart ass
@kabayanhustler7 жыл бұрын
Don't forget the sexy elastic curve.
@domesday15357 жыл бұрын
I think we all know this is missing a crucial axial force diagram
@jeffmoncalieri74913 жыл бұрын
skip to about @2:30 to see anything happen.
@anthonyhitchings10512 жыл бұрын
I and my colleagues did this back in 1973 at Eng School in Auckland, NZ
@edwardcornell12632 жыл бұрын
I did this in 8th grade.
@parttimelaowai17712 жыл бұрын
@@edwardcornell1263 I did this before my first birthday.
@ChakatNightspark3 жыл бұрын
its kindof weird load putting on it. two small spots. instead of doing it over a larger area
@gowdsake71036 жыл бұрын
I like the way they all have hardhats with fuck all to fall on their heads and yet no screens between them and the beam
@stephenmiller90096 жыл бұрын
gowd sake you basically wear what the main guy in charge wants to supply
@darkshadowsx59493 жыл бұрын
does a reverse arch do much? seems pointless other than adding mid span mass. i need scientific data on that.
@user-dq7ms8ir4c3 жыл бұрын
absolutely, truss joists on most shopping centers are guilt the same way. The bearing point on girders is minimal. Go into ,Home Depot and look up.
@johnstuartsmith2 жыл бұрын
Quick, Bob, put some spackle on that before the inspector shows up...
@Randyphx2 жыл бұрын
That's a solid win for them. Great job guys!
@botchedonce71596 жыл бұрын
Say no to crack.
@gordbaker8962 жыл бұрын
CoreSlab is nearby. Please put PSI/SAE values in as well as n/m
@fredschmidt31483 жыл бұрын
I was expecting a more catastrophic failure.
@casb24803 жыл бұрын
The whole idea about designing safe concrete structures is to avoid catastrophic failure. A well designed concrete part is going to greatly deform before eventual failure of the compression zone (this is beautifully shown in this example actually). The whole idea about this is that it gives of a warning effect leaving time to evacuate the structure when it is overloaded or failing. When a beam instantly breaks, it could indeed be a lot more catastrophically!
@mrb6923 жыл бұрын
It also has to do with how the load is applied. Unlike a hydraulic press or something where the force is always applied, here, the force is applied because the block is being driven down by giant jackscrews at slow, fixed rate. It couldn’t shoot down even if it wanted to
@joeseabert83917 жыл бұрын
My brother did something similar to a V tail bonanza using bags of lead shot. Caused Beechcraft to implement a design change.
@knothead1fersure3033 жыл бұрын
High tech ,fully equipped, state of the art , crack analysis right there.
@EngineerPEretired7 жыл бұрын
I read all the PPE complaints...Obviously, they do not understand PEE requirements...for example, steel toed shoes are not required unless a toe crush hazard exist. You know your test and what hazards exist...they (complainers) need to relax... Thanks for sharing your test; with that said, please, share what reinforcement was used and also the PSI of the concrete materials. Thank you kindly, in advanced... PS Would you have a detail of that in another video?
@auggieaugbourn47887 жыл бұрын
You can do what you want in Philly. But Ontario law requires them to wear glasses steel toes and hard hats. Not to mention the lack of barricades and warning signs. Labour board inspector shows up shuts the lab down and fines everyone involved.
@EngineerPEretired7 жыл бұрын
So, you are telling me, in this school environment and NOT a workplace!... that your "labor laws apply"? That sounds like you do not understand this is in school and not a ''work area"... I will accept being wrong... but, please, send me the link that shows that... peace!
@auggieaugbourn47887 жыл бұрын
Philadelphia Construction Engineering it is a workplace. The instructor is being paid, it's his workplace. That and you'd sue this shit out of the school if your kid lost an eye or worse while this test was being done. As for the law , look up the Ontario occupational health and safety act. It's all there in black and white.
@EngineerPEretired7 жыл бұрын
WHAT? The ''kids'' are adults! This is a university and this is not in the first year program (99%)... The instructor would have to report himself or someone like you would have to call on the school -- to make this complaint... The instructor could call on himself also - what? Ultimately, the hazard has to be there... the instructor would clearly be able to show, that no eyes were lost in his ''hundreds'' of test-- therefore, the ''hazard'' is not present... Of course, it is always more safe... the better... But, you snowflakes are getting all bent out of shape...
@auggieaugbourn47887 жыл бұрын
Philadelphia Construction Engineering there is all kinds of hazards in this test. 1 The beam had to be craned off a truck and installed on the test bed. 2 prestressed cables can and will shoot out of the beam if the tension is released rapidly.( 15 years of heavy concrete demolition experience. I've seen it happen.). 3 These people or going to be engineers crawling around construction sites they should be trained to wear the proper PPE. In Ontario glasses, boots, hardhat and highviz vests are the minimum requirements to enter any construction site. 4 if anybody on that site is killed or seriously injured during the test the supervisor is liable and will be tried and fined up to $100000. The employer ( the university) is liable and can be fined up to $250000 not including any civil penalties. The Labour board inspector can't be everywhere but if something happens the penalties can be severe.
@ImNotPotus8 жыл бұрын
Just so I am clear on this concept. The Univ. of Toronto will threaten to terminate a professor for not using bigoteer pronouns but is totally OK with a professor not having anyone use PPE (Safety Goggles) for a potentially hazardous test. I get it that the cracking was slow but how did they know that the beam was cast properly? It could have failed catastrophically and sent shards of concrete chips flying into eyeballs. WTF is a hard hat going to do for lateral projectiles??????
@drink158 жыл бұрын
It's wasn't needed for that kind of test. But you do see the guy closest by the screen put them on at one point.
@brendanboyer57608 жыл бұрын
First thing I noticed. I've never seen a work environment where a hardhat is necessary but safety glasses aren't, including this video.
@drink158 жыл бұрын
Brendan Boyer Construction sites (if no one is working), some factories. There are many places. Eye protection is only need if there is a risk of eye injury.
@schizoidman1437 жыл бұрын
They're highly unsorted engineers
@richavic45207 жыл бұрын
SchizoidMan does that also mean they are well graded?
@besearchingforwisdom62673 жыл бұрын
It is notable that the amount of deflection just before the final failure would be clear and evidence that corrections and other safety strategies would give plenty of notice to implement an orderly plan take. Unless of course it occurred swiftly, like for example when my stepmother was the culprit
@Tinas2Labs6 жыл бұрын
yeah, Im just gonna sit here 5 feet away from this fkn thing, no containment devices, nuthin but a hard hat.....till it implodes, really
@bob21613 жыл бұрын
So long as you're not inside the beam when it implodes, you're golden.
@DR.ELEKTRIK7 жыл бұрын
No eye protection?
@ffjsb3 жыл бұрын
No safety glasses, no protective barrier between the test equipment and the desk and monitors... Seems these "engineers" are ignoring BASIC safety concepts.
@stevendegreef933 жыл бұрын
Maybe they just seem to understand the nature of these reinforced concrete failures just a tiny bit better than you? Possibly? 👀😎
@percival233 жыл бұрын
@@stevendegreef93 Maybe he understands the benefits of managing risk just a tiny bit better than you? :)
@shanesooth62673 жыл бұрын
@@stevendegreef93 If you ever stressed post tension cables you would understand how dangerous and unpredictable a blow out can be.
@stevendegreef933 жыл бұрын
@@shanesooth6267 Those are springs. Free steel under tension. Completely different animal. In this case all steel has been encapsulated with concrete, there s just no way that all tension on the steel can be released at once. Or does your imagination see all the concrete letting go of all the embedded steel at once? (footage contradicts you) (you must be right, these engineers are soooooo dumb.... 😆)
@shanesooth62673 жыл бұрын
@@stevendegreef93 you don’t need to be a smart ass behind your keyboard. I may be wrong but from what I read in the description it says nothing about a encapsulated steel beam it’s does say prestressed concrete beam. I have built similar beams for DSI when I was a local 416 IRONWORKER in Los Angeles. I am retired after 31 years placing rebar.
@buggz06157 жыл бұрын
in real life their is alot of vibration on beams dose your test account for this or is it strictly load
@FairladyS1303 жыл бұрын
Main cracks started at the two load points, who wudda thunk.
@MrZoomZone3 жыл бұрын
and the beam was shaped with the load points in mind.
@FairladyS1303 жыл бұрын
@@MrZoomZone Not 'shaped' enough then.
@mrl222223 жыл бұрын
@@FairladyS130 it would depend on the design load. Perhaps this was already 200% of the3 design, so it performed well at that point.
@pavanatanaya7 жыл бұрын
How green was this concrete. Age/days? Wouldn't you want a few test beams at 7 day intervals from the date of pour to test the failure curve? Just asking.
@romeoETmike3 жыл бұрын
they tested it on the 28th day.
@Cloud-zq8mf3 жыл бұрын
Welcome to the hydraulic press channel, and here we go,
@JeffMTX3 жыл бұрын
holy shiit!
@majidkhodier89776 жыл бұрын
Is this a hollow beam?? If the pressure was applied at one point in the center, the beam would fail earlier!
@OtherWorldExplorers8 жыл бұрын
Neat test but... Safety anyone? No one with proper eye protection... tools left in the test area (screwdriver in lower right)... no designation for danger area....
@domesday15357 жыл бұрын
These don't tend to be that dangerous to be around. But it is still good practice
@madrx27 жыл бұрын
Won't someone think of the children!!!!!!!!
@docducttape92706 жыл бұрын
madrx2 it's all fun and games until someone looses an eye! 😉
@fusspot577 жыл бұрын
I like the smattering of applause at the end......jolly well done beam!
@peterjensen68446 жыл бұрын
Anyone else notice the TV screen image drifting around during the sped up video?
@wheresfuninthat6 жыл бұрын
Peter Jensen yes.... wtf.
@TD_YT0663 жыл бұрын
Maybe to prevent screen burn since the image is fixed.
@peterjensen68443 жыл бұрын
@@TD_YT066 yeah that seems to be the logical reason when you have those fixed box elements
@RoaringOrange3 жыл бұрын
2:20 why is image on monitor shifting left and right?.......
@pmolz3 жыл бұрын
To prevent burn-in, it likely displays the same image all the time so they cycle the pixels to keep them working
@akhilmt97313 жыл бұрын
@@pmolz will the burn-in occur even if the screen is LED?
@pmolz3 жыл бұрын
@@akhilmt9731 With normal use, no, but they may suffer from temporary image retention which goes away after awhile