Understanding Stresses in Beams

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  • čas přidán 29. 06. 2020
  • In this video we explore bending and shear stresses in beams. A bending moment is the resultant of bending stresses, which are normal stresses acting perpendicular to the beam cross-section. We can easily derive an equation for these bending stresses by observing how a beam deforms for a case of pure bending. This equation is know as the flexure formula.
    Next we look at shear stresses, which act parallel to the beam cross-section, and can be represented by a shear force. These vertical shear stresses can cause horizontal shear failure in beams, because they result in complementary horizontal shear stresses, which develop to maintain equilibrium.
    Finally we look at how we can apply the shear stress equation to thin-walled open sections like the I beam, and how shear stress appears to "flow" through the cross-section.
    ---
    ERRATA:
    - The moment shown at 07:38 is drawn in the wrong direction.
    - The shear stress profile shown at 11:41 is incorrect - the correct profile has the maximum shear stress at the edges of the cross-section, and the minimum shear stress at the centre.
    ---
    If you would like to support the channel, please consider becoming a Patron - / efficientengineer . This will allow me to create more high quality videos covering a range of engineering topics.
    ---
    The Efficient Engineer is a channel aimed at mechanical and civil engineers. The mission is to simplify engineering concepts, one video at a time!
    Follow me on Twitter: / efficiengineer

Komentáře • 1,1K

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    @iliasproko7341 Před 4 lety +421

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    • @ihaveseverefrootsnackism
      @ihaveseverefrootsnackism Před 3 lety +8

      Third year civil as well! xD
      Never completely understood moments, INSTANTLY understood them after this video. Incredible.
      I had a terrible statics professor.

    • @littelcreatchure506
      @littelcreatchure506 Před 3 měsíci +1

      I'm 2nd year and using these to help me pass my mechanics class

    • @nithyavardhan3474
      @nithyavardhan3474 Před 2 měsíci

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    • @TheEfficientEngineer
      @TheEfficientEngineer  Před 3 lety +62

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    @rupanzilmamunprince Před 3 lety +235

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      That was a “mind blown” experience for me

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    @GeniusEngineering Před 4 lety +395

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    @kylesteele5848 Před 4 lety +2081

    imagine if university professors taught us like this

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    @ryanfranz6715 Před 2 lety +7

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      @michaelbodine6142 Před 2 lety

      MIT designs tools, they are heavily verbose AND very thorough.

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    @guptasagar694 Před 4 lety +47

    This video is a true treasure for engineering students from South Asian poor countries like INDIA because we not only lack quality faculties to teach us but also basic laboratory experiments are not possible to be done for 99% Indian engineering students, they just know how to mug things without even actually realising the depth of subject and how to apply it in real life...thanks to intellectuals from USA .

    • @azithral4057
      @azithral4057 Před 4 lety +1

      bruhh hes from UK

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      @@azithral4057 Bruhh, that's an American accent.

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      @ihaveseverefrootsnackism Před 3 lety +1

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      There's a couple exceptions.

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    me, eating jelly beans at 3:30am
    youtube algorithm: hey, wanna learn about beams?
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    I can't imagine the time and effort you put in making these videos. Thank you

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    @abheethsatharasinghe2490 Před 4 lety +130

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      Exactly .in India educt sucks

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      @HarshRajAlwaysfree Před 2 lety

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      We learn more on CZcams than these professors

    • @abithakur9040
      @abithakur9040 Před 2 lety

      @@HarshRajAlwaysfree right bro they r just book worms and they don't teach what is happening currently in industries ..thats y India lags in skills ..

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    @benha4334 Před 3 lety +7

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    @chrisjuengling1983 Před rokem

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    @ankushkurmi3741 Před 3 lety +1

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    Thanks a lot for putting the subject into so simpler words

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    I love your videos the why you explain, animate and edited the videos is remarkable and I have worked on animating my presentation based on ideas I toke from your videos and now I know how much work you have put in them thank so much for the motivation and I hope, that I can some day present engineering lectures as you

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    I really like the animations. Explaining concepts visually makes them easier to understand. Keep up the great work!

  • @shuvradev2207
    @shuvradev2207 Před 2 lety +1

    Can't show how much grateful I am to you!!! I was just doing the problem and struggling too much visualizing the stresses. Your videos are life changing. Please continue supporting like this. Take lots of love boss. Salute

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    @filipgenovski Před 3 lety +3

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    @jamescyriacajith Před 4 lety +2

    The best explanation for bending and shear stress, complementary horizontal shear stresses
    , I beams on youtube. I wish I had access to these material during my engineering program.

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    @nasmboyd1573 Před 3 lety +2

    finally a video that explains better than professors and helps me to understand my course way more efficiently

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    @ethanmcdonald7922 Před 2 lety +2

    I graduated mechanical engineering a year ago, but it is still good to always review content like this. Thank you

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    @minkymott Před 4 lety +3

    I have zero math capabilities, but even through all the formulas I understood the meaning. And the way you narrate is very calming. You have a great narrating voice. You're really good at this. Thanks for posting.

  • @nithishprabhu
    @nithishprabhu Před 3 lety +5

    Thank you!! It's the best explanation ever for the folding/unfolding of beams! Able to explain complex phenomena in simple words without throwing in big terms is a talent. I wish someone would teach the same mechanics concerned to composites.

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      @akshaymahawar1781 Před 2 lety

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    @markspc1 Před 3 lety +2

    Great instructional video.
    It takes most structural engineer ten years on the job to understand beam shear stress !

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    @gnidnoeled786 Před 3 lety +2

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    @johnpaoloconstantino5626 Před 4 lety +4

    Amazing work as complement to the book Strength of Materials (Pytel, Singer). Brushing up on my structural design/theory knowledge. Every bit of resource counts during these trying times esp. with the students. Thank you and kudos! -Civil Engr. from the Philippines

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    @khairulanam4632 Před 3 lety +3

    This is so easy to understand considering the amount of formulas used in this chapter.

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    @alexhollis3755 Před 3 lety +1

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    MoM final exam is just around the corner, so blessed your video come in time while i started to open my book to revise this topic lol 😂

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    @NutsandGuts Před 3 lety +2

    A beautiful explanation. Especially on the Jouravski shear part. Thank you so much.

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    @aion2177 Před 3 lety +1

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    @owenhurley2315 Před 3 lety

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    @ssuk_milk Před 3 lety +13

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  • @kmmjcx
    @kmmjcx Před 3 lety +1

    Watching videos from this channel after reading it from the books totally helps me solidify the understanding. More power!

  • @philjohnson3547
    @philjohnson3547 Před rokem

    It is 40 years since I was first taught this stuff. I wish I has these videos then. The graphics really help the understanding of bending and shear stresses in beams. Young people learning this for the first time probably don't realise how lucky they are!

  • @GaniEmi
    @GaniEmi Před 3 lety +9

    oh man, i used to know all this and it was easy, 20 years later i cant remember most stuff

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    @desiredditor Před 3 lety +12

    Keep making actual engineering content not like some other channels who gloss over sums & make theory

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    @TheHowtoDad Před 4 lety +1

    I have a degree in civil, this was a super helpful. It is often difficult to visualize what is happening with internal stresses, this helps package everything up for me.

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    @ken-cf7tf Před 3 lety +2

    I really appreciate your videos! Youre really making concepts so much easier to understand. Please do videos on mechanics or thermodynamics too! :)

  • @kingmasterlord
    @kingmasterlord Před 3 lety +6

    this video reminded me what it felt like as a kid to enjoy math

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      @savage22bolt32 Před 3 lety +1

      I suck in math, but I wonder about things like this all the time, so I found the video very interesting.
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    The title of this channel 'The Efficient Engineer' really suits you.

  • @rahmanrahmani2896
    @rahmanrahmani2896 Před 4 lety +1

    Outstanding presentation and as a result of to appreciate these phenomena within the structure due to loadings. Thank you!

  • @SheriCoco
    @SheriCoco Před 3 lety +2

    Fantastic explanation. I always make sure to share it with my course mates because everyone needs to get this simplified awesomeness

  • @Baso2014
    @Baso2014 Před 4 lety +3

    Thank you very much for the clear explanations and visualizations. Could you please tell us what software do you use to produce such stunning graphics and animations?

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    @hamza_ME_ Před 4 lety +8

    I have this course next semester...
    But I'm still gonna watch now

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      @imperialchaos8143 Před 3 lety +2

      I have an exam on this in 2 days… guess there are 2 types of students

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      @samisiddiqi5411 Před 2 lety

      @@imperialchaos8143 I am both LMAO

  • @TheAviationChannel
    @TheAviationChannel Před 2 lety +2

    You literally explained in 14 mins what my lecturer explained in 14 days. Thanks for this video

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    @TienNguyen-mc5hk Před 2 lety

    This video clip is an excellent resource for engineering education. I wish I could have known it when I was in school, my understanding could be speeded up much faster rather than I spent so many hours in classes.

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    @o_jungio Před 4 lety +3

    This is God-given content. I can't thank you enough.

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    @7anashMalaysia Před 3 lety +3

    Brother... I just understood what I couldn't understand in my 4 year Civil Engineering studies

  • @brianolivo1835
    @brianolivo1835 Před 2 lety

    This is one of the best videos I have ever seen on bending and shear stresses!

  • @sluffnut7507
    @sluffnut7507 Před 2 lety

    You explained in the first 5 minutes of this video what my prof couldn't explain to my class in a month. Thank you

  • @patecillo19944
    @patecillo19944 Před 4 lety +8

    Could you do a video about fracture mechanics, it is a very interesting and hard topic

  • @niklip007
    @niklip007 Před 3 lety +4

    Amazing video and great explanation indeed. Thank you so much for the effort! Just a small comment at 7:40, for the moment you apply on the left beam, the deflection should be mirrored (tension side on the bottom). Keep up the great work! All the best

  • @miguelamartinez1411
    @miguelamartinez1411 Před 9 měsíci

    It is a great felling to come back to these topics, by listening to a well explained lecture like yours. An engineer graduated in 1990.

  • @kshitijvermacms
    @kshitijvermacms Před 3 lety

    4 hours boring lectures by proff < = 15 min video bcaz of this creater and main point is its absolutely free... thanks a lot. Pls keep it up

  • @jurajturansky413
    @jurajturansky413 Před 3 lety +3

    holy shit I just understood what am I studying. This is great visualisation tool.

  • @PATHMINDER
    @PATHMINDER Před 3 lety +3

    Thanks for this vid.
    But I guess/remember:
    Interaction between shear and moment is taken in account in steel beams.
    ..They reduced moment capacity(resistance) in some cases.

  • @daniloorbolato
    @daniloorbolato Před 3 lety

    This is top notch man. So much clear info in so little time.

  • @SANSKARGUPTA-oz5gc
    @SANSKARGUPTA-oz5gc Před 10 měsíci

    This is the most beautiful video explaining these terrifying terms. Love ur work bro..

  • @frikkieramabolo172
    @frikkieramabolo172 Před 4 lety +15

    When are we getting video's on other engineering subjects like Thermodynamics, or Fluid dynamics?

    • @TheEfficientEngineer
      @TheEfficientEngineer  Před 4 lety +46

      Still figuring out what I want to do next, but it's likely the next video or two will be on fluid dynamics.

    • @frikkieramabolo172
      @frikkieramabolo172 Před 4 lety +2

      @@TheEfficientEngineer That's great! I'm looking forward to it!👍👏

    • @porschepanamera92
      @porschepanamera92 Před 4 lety +2

      Structural dynamics is also interesting!

    • @babajungLA
      @babajungLA Před 4 lety +1

      @@TheEfficientEngineer Yes Please! You can make atleast 10 videos just on fluid dynamics lol. And ofcourse Thermodynamics is also a vast subject - looking forward to hear about enthalpy and entropy!

    • @aliasgeranees8893
      @aliasgeranees8893 Před 4 lety

      @@TheEfficientEngineer maybe you can try topics like dynamics of machinery... I haven't found anything good on the subject on net... There are plenty of fluid mechanics video already so.. Just a suggestion... Love your work... May God give you strength to continue such good work

  • @Calm_unbothered_af
    @Calm_unbothered_af Před rokem +3

    cant understand a single thing (not yr fault though) but yeah nice animations

  • @plantae420
    @plantae420 Před 2 lety

    I love mechanics.
    It explains most of our everyday experience and it’s axioms are simple but powerful enough to derive a great amount of complexity that causes endless amount of new stuff to learn and becomes therefore never boring.

  • @uss969
    @uss969 Před 3 lety +1

    I have no words for this beautiful explanation
    You explore beauty of physics

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    @jesserramsessoller990 Před 3 lety

    This is one of the best educational channels I've ever found.

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    Hats off sir, such a great example of conceptual explanation and visual representation. Appreciated!

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    Great job dude. Your videos are helping out many engineering students to get the concept. Thank you!

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    @karasirarichard3358 Před 4 lety

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    @souvik.fingtore Před 4 měsíci

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    @naveenkarkiful Před 3 lety

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  • @ahmedafrah7869
    @ahmedafrah7869 Před 2 lety

    before ididnt get the clear image of shear stress along vertical and horizontal....but now ..with the help of this video i got it ....thanks lot...i salute you sir

  • @kamleshkulkarni6522
    @kamleshkulkarni6522 Před 3 lety +2

    That was very thorough and beautifully explained.

  • @sstoor908
    @sstoor908 Před 2 lety

    Better than the two hr lecture I had. Animations are the best way to understand