How to identify zero force members in trusses

This engineering statics tutorial explains how to identify zero force members in trusses. Please note that when I’m erasing members, I’m not “removing” them. They’re still there. I’m just erasing the ones identified to be ZFMs so the joints are less cluttered, and it’s easier to identify more ZFMs. Zero Force Members have purpose: for bracing, rigidity, and if the loading changes, the internal forces in each member will change, which means that different members will be ZFMs at different times. This problem is wildly simplified compared to a real life scenario, but is useful for teaching students about the concept and identification of ZFMs.

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Thanks for watching, I hope it helps!

[kylehaase]

I got a final that counts for 50 percent of my grade tomorrow, and these vids are definitely helping me grasp the concepts much better.

[himanshukumarsingh]

I covered the whole truss topic watching your videos and learnt the whole thing in just an hour whereas my professor covered the whole topic in 2 weeks and even after that I had no idea what was going on in the classes.
Thank you so much sir.

[voicevoicelessKrzysiek]

I'm reading the book "Structures" by J.E. Gordon (I am an electrical engineer) (I think it was on Musk's important books list) and it made me wonder about trusses so that's how I got here. This video and others on the trusses subject by Engineer4Free I found very well presented and easy to understand. I appreciate these free tutorials a lot. Thank you very much, Engineer4Free!

[soliewx]

Just wanted to say, even after 7 years your video is helping people! I am currently studying for my FE exam and structural analysis was always hard for me but this video makes it so easy to understand. THANK YOU

[patrickgullia]

you're description was phenomenal. the other videos don't explain why...good job

[csyoung]

I'm studying for the Structural Systems component of my ARE and this is by far the most succinct explanation for identifying zero force members. Thank you so much for this video.

[Kyavata]

I'm a truck driver, why do I need to know this? What has YouTube done to me? Is it technology or civilization that has jumped the shark? I don't even...
Also: excellent video.

[alsubaihawiful]

Thank you! Very clear and easy to follow. I'm taking the Civil FE exam in one week from today. I will update you on the zero member question after the exam.

[guitarmyart]

Thank you for uploading these videos. I felt like I never understood any of this in school, but you make it so that its understandable.

[nlo]

This is great in terms of pure mathematical vector addition. The 'zero-force' members are there because in the real world, the minimum net is not physically perfect. Heavy wind-blown drifted snow on one side upsets the equilibrium of the 'perfect' net. Remove the zero-load trusses, the roof collapses.

[lochtlmao]

sitting in my halloween costume trying to learn this before my exam tomorrow

[jarrredl]

Got a statics final in 4 hours so this will save my grade, thanks

[larkzproduction]

You’re a Legend, swear to god I can’t understand my lecturer but your videos clears everything up...🙏🙌

[stormykat]

Thank you so much, this really helped me understand the concept of zero force members! I was having a lot of problems analyzing trusses because I couldn't figure out which members were zero force members (my professors lecture slides were rather unclear) so I got lost trying to figure out free body diagrams for the more complicated trusses and this video helps so much!!

[adexfunkyadex]

Finally understand zero force members teach made it so damn hard but your explanation was amazing

[adewalekehinde]

Waoh, so easy . Thanks for explaining in a simple way. Teaching shouldn't be difficult.

[gdsmck]

What I don't understand is why the member underneath the applied load in the first member is a 0 force member. If there is a vertical load on it, shouldn't there be a compression force on it pushing on the two co-linear members perpendicular to it, therefore not making it a 0 force member?

[tiffanypersaud]

Got a test Monday. You're saving me!

[danialalkhoury]

Very nice video and explanations, have to add something for the last zero force member in the video... it is possible to remove it in order to get the right answer, however it can't be removed from the structure since it is supporting the rolling element that would fall downward... so yes you can solve the problem, but don't draw it like that because I won't make sense.

[Holsink]

This is a really good video, you saved my exam, thank you