Static Determinacy, Indeterminacy and Stability of a Plane Frame - Solved Examples

[@AFMathandEngineering]

Let us know if this video helped you, and what you want to see next! Link to space truss video for indeterminacy! kzbin.info/www/bejne/gqCxc35sabx_pMk

[@aseelabdulrahman1510]

we will take (deformation) plz do video for this subject :)

[@AFMathandEngineering]

Cool, thanks! Stay subscribed and let us know when it comes up or more specifically what you want to see and we'll do it :D

[@trentonmartinez2476]

Studying for the FE and this was a great clear and concise review. Thank you!

[@PegasiJay]

Same here. good video.

[@ImanHarsini]

same here. it helped a lot.

[@iChaseShotsWithMayonnaise]

Your explanation of this concept was so much better than my professor's. Thank you so much, I'd been overcomplicating things without even realizing it!

[@cinnamonspice2897]

I love the sheet you made! It made understanding the degree of statical indeterminacy a lot easier! Thank you for putting time into this and sharing! :)

[@kristina1644]

Best explanation i found. Thank you so much so clear and to the point

[@gh5030]

Very useful, much much better than my professor.. thank you so much..

[@meeelaaad]

Always had problem in counting members and joints.Thanks

[@mienge2177]

Hi, can you please explain that can you count the beam or columns with the hing in the middle as 1 (beam or column) instead of counting as 2 members if so can you explain different approaches. Will they give the same answer or counting 2 members is right? I am a little bit confused. Thank you.

[@cosine5612]

2:05 As what I have learned, overhang is not considered as a member. May know why did you count it sir?

[@kimhao98]

Thank you man! I remember this video and it saved my test!

[@AFMathandEngineering]

Great!

[@karlayericksoriano]

it helps me! Thanks

[@clarence__]

Thank you ❤

[@jervisyeo]

Hi for plane frame for the determining of the internal forces do u exposed the forces by cutting in either the vertical or horizontal direction but not both?

[@sallymowafaq6355]

Good job

[@manikantagodi3239]

simply awesome...please do more videos

[@AFMathandEngineering]

mani kanta godi thanks man appreciate it!

[@Joff_Joff]

Well done video, keep up the great work!

[@AFMathandEngineering]

Thanks so much for the great feedback, appreciate you stopping by and leaving a comment!

[@miguelsoto3892]

Thank you much!!!

[@TanvirAhmed-xr8il]

thanks great video

[@AFMathandEngineering]

Thanks for the comment!

[@shahadjz2]

THANK YOU

[@Doritos15409]

im confused! my prof said that internal internal hinge was not count as a joint but then you include the internal hinge as part of the joint. So what is right?

[@AFMathandEngineering]

I replied to another comment on this, for our reference please refer to 4th or 5th edition of structural analysis by kassimali, they do refer to internal hinges as joints. This of course makes sense, as an additional reaction is generated as a result of an internal hinge. In engineering in university however, sometimes you have to just do what your prof wants you to do in order to get the mark, despite it being possibly wrong. Please refer to this textbook though to confirm that what we're doing is correct for yourself; it's easy to find a PDF online and it's a very well known textbook in structural analysis.

[@avizopfukri518]

Does this also apply to pin jointed frames?

[@mstchmshrms9214]

Does this work when not all of the supports are on the same plane? For example I have one that looks like a peace sign, the one on the left is a pinned support and the two on the right are roller supports. THANKS!

[@AFMathandEngineering]

You mean in the y axis? Yes it still works.

[@ummokay]

u r the best

[@AFMathandEngineering]

Thanks! :D

[@SidharthMishra99]

How Can we find out extra equations on the basis of Static Indeterminacy What are that extra reactions,explain us with examples

[@AFMathandEngineering]

You'll learn the different methods and the differences between determinant and indeterminate in 2nd or 3rd year of your engineering degree. We have tons of examples on our channel of both, feel free to look through our structural analysis playlist.

[@SidharthMishra99]

@@AFMathandEngineering Ok Sir

[@muhammadhashim73]

why are you not counting reaction on internal hinge???

[@antonystephen143]

Hallo sir... Can u also do an example on how to determine determinacy in 3d structures

[@AFMathandEngineering]

Antony stephen hey, thanks for the comment! The difference between 3d trusses such as a rigid frame or space truss and plane frames is the number of equations of equilibrium available. In plane frames in this video we have 3 equations of equilibrium, for 3d we have 6 equations. The equation for 3d becomes m + 6 = 3j for determinant 3d frames. Hope that helps, and when we have time we'll make a video on it! Cheers.

[@antonystephen143]

I hv a problem in determining the number of reactions present within the 3d structures. I was hopping to know how I could determine the numbers of reaction otherwise determining the number of hinges, members and joints I have understood from your explanation.

[@AFMathandEngineering]

Antony stephen thanks for letting us know your issue, we appreciate it. We will make a video on this topic for you, make sure you have notifications on when you subscribe and you'll get an update when it's ready!

[@antonystephen143]

Thanks a bunch

[@antonystephen143]

Sorry for being impatient but please static determinance of 3d structures examples....I'd appreciate it

[@yatri6352]

What are two condition equations if a internal hinge exist connecting 3 members and so on? please anyone tell me.

[@martaottinbocat1641]

Hi sir, can you please give a quick explanation about how to determine the reaction?

[@AFMathandEngineering]

There are a number of methods, check our videos on trusses

[@staskouzmine]

What would be 'stable'. On my exam we had to choose some stable, unstable, determinate and indeterminate. Would stable just be determinate and indeterminate?

[@AFMathandEngineering]

Good question, can't remember if we mention it in this video but unstable means you have less reactions than number of equations. So an example of this would be a beam with two rollers. There's only two reactions ( both in y ) but three equations ( sum of forces in x, y, and sum of moments = 0). You can imagine that a beam with only two rollers would be unable to resist any forces in x and is unstable. Anything either above or equal # forces = number of equations is considered stable.

[@AFMathandEngineering]

To add to that, you can now see how a beam can be stable and determinate (3 reactions 3 equations) and indeterminate and stable ( 3 equations, more than 3 reactions ). So it isn't just a question of determinant or not.

[@staskouzmine]

@@AFMathandEngineering That makes sense thank you! Didn't expect such a quick reply!

[@AFMathandEngineering]

No problem!

[@markledbetter5960]

Yeah that is not consistent with West / Geschwinder (Fundamentals of Structural Analysis). Ends are not counted as joints and members are not counted as two when separated by an internal hinge. Or I am missing something. Pg 156 of the textbook.

[@vavacita]

Great video! How did you get 6 reactions from second one?

[@aether3697]

The supports are fixed. Each fixed support got 3 reactions

[@shianrilongreamei2935]

e.c is this what we call as Force release?

[@eugeniojimenez7268]

where did the 6 reactions come from

[@antonystephen143]

Understood. I never meant it in a hostile manner.

[@AFMathandEngineering]

Antony stephen didn't think it was hostile at all, just don't want you to get your expectations up that we'll complete your requests quickly! Wish we could do them faster but we're pretty busy :D We appreciate your engagement on our channel! :D

[@AFMathandEngineering]

We finished and uploaded your request antony, let us know if it helped you :D

[@MrGunit1789]

This was a great video but could be better. Your explanation of "r" was not really an explanation. I tried to do the second and third question based on the first and I find "r" to be different each time.

[@AFMathandEngineering]

Hey, thanks for the feedback. This isn't really a video on determining reactions of different support types, that's one of the first things you learn in statics and mechanics of materials so it was assumed to be known here. Perhaps we should make a video on this topic exclusively.

[@hijack8752]

why is it sir that there are no joints in the last example?? I thought there are 15 joints.

[@AFMathandEngineering]

+Hi Jack for the last example there's still joints members and reactions, but as I mentioned in the problem, if you have a rigid frame that's fixed with no hinges you can use the trick that the degree of indeterminacy is simply the number of girders times 3. Thanks for the comment!

[@AFMathandEngineering]

Hi Jack try solving it using the method from the first three examples, you'll see that you arrive at the same answer. m=20, r=9, j=15.

[@shoryuguten]

If the frame is indeterminate do i still solve it

[@AFMathandEngineering]

This video is not about solving frames just identifying indeterminacy degree. In real life most structures are indeterminate and require computer software to be solved in a reasonable amount of time. You can solve them by hand but they make a long time I'd they are of a high degree of indeterminacy.

[@ingrid4102587]

Hello Sir, I was wondering how to calculate the reactions? The voice in this video wasn't very clearly,I can't hear it very well. :D

[@AFMathandEngineering]

劉怡彤 this video is not about reactions. We have other videos on this topic, if you're interested.

[@ingrid4102587]

Thanks!

[@AFMathandEngineering]

Cantilever beam with hinges: kzbin.info/www/bejne/aWK4qomDqZeUidE Simply Supported w/ Cantilever: kzbin.info/www/bejne/ZmKag3WjdpVme80 In many of our videos we solve for the reactions first, you can search for more in our videos section :)

[@jaym8476]

you count the second one 7 members but you write down m=4

[@onur-9158]

what if there is an external force.

[@AFMathandEngineering]

External forces don't affect the internal determinacy of the structure.

[@bassitbaba6955]

thank u

[@AFMathandEngineering]

thanks for the comment!

[@rachaelgreene4973]

i dont understand how you got 6 reactions on ex 2

[@AFMathandEngineering]

A fully fixed support is restrained against 3 forces, Fx Fy and M. There are two fixed supports. I'd highly recommend becoming very familiar with reactions in 2 and 3d as it's extrmely important in school and in real life work.

[@aseelabdulrahman1510]

we did not study like this at all the relase moment or (hinge) dosnt takeing in joint numbers !!

[@AFMathandEngineering]

According to how we studied, including according to Structural Analysis by Kassimali the method shown in this video is correct. Please email me at [e-mail] if you'd like me to provide you more info :D

[@aseelabdulrahman1510]

i have exam after a few hours later i did not now belive who , you are or my dr 😂😂

[@AFMathandEngineering]

Email me, I'll show you something to prove it :D

[@AFMathandEngineering]

However, in engineering in school...even if your professor tells you something that's wrong it's best to do what they say...especially if they're the ones marking it. If your professor told you to do something a certain way, do it that way.

[@j.wick.30yearsago48]

How the hell is he finding reactions

[@AFMathandEngineering]

We skipped that explanation because if you're at this point it's assumed you know how to find reactions of pins/rollers/fixed supports. Check our other videos on how to calculate # of reactions.

[@rosemariemira1499]

Thank you so much for your help 😊