I dont really leave comments, but this video made this sooo clear! when you repeat stuff and add sounds really helps me focus! thxs U got a new subscriber!
Simply explained on the theory to better understand. I went to the 9th IVY L school abt 30 years ago. And you are better at explaining and more fun. To be safe for column design , I would limit the ratio of ultimate axial stress over the F'c to 0.4. This will limit the max. steel bars to abt. 4% and avoid congestion at lappings.
Hi Dr. Tyler. This is brilliant- you explained it so simple and straight forward. Any chance you can do a video on a Pushover analysis? In fact any videos available on bridges will be awesome
I see it this way - if you design something then the best option would be to design it for a controlled failure. Imagine a bridge - if the ramp to the bridge fails at a lower load than the bridge, then the result would be less severe, especially if the design just causes a minor depression at a safe distance from the bridge. It could also serve as an indicator for maintenance where when some insignificant part breaks it's a sign that the structure has aged to a certain level and needs an overhaul. So sometimes failure is an option.
Dr Ley thank you so much for this informative video. Really filled in a knowledge gap I was trying to fill. The Four Critical Points: are we supposed to design the column based on these 4 cases? We must ensure that the column has enough capacity to fulfill the 4 cases?
Do you mean phi for concrete or phi for the steel? Canadian code has phi=0.65 for concrete and phi=0.85 for steel. This is much simpler and gives practical results. I can see phi jumping to 0.7 for the concrete in the ductile zone and phi for steel jumping to 0.9 but I think that needs to be more clear.
Actually it is Sigma y [N/mm^2]= My [N*mm]*z [mm]/Iy [mm^4] at 0:28. Or Sigma y=My/Wy. @1:04 you just cannot sum or subtract N/mm^2 with N/mm^3. Nice explanations anyway!
Just only two stress in structure work in the difference way namely normal stress and shear stress. axial,bending are normal stress can be compression or tension or combination of them.
I will never understand why modern engineering is using straight bars in beams, its more logical to use steel wire rope , atleast add it in the middle, pour concrete over it while its loose in curved hanging shape, and under heavy pressure load will be eaqualy distributed, it simulates curved shape of a bar in failure, so the whole beam elastic deformation part is just skipped, result is when it fails it just snaps and thats it, without any cracks or curving deformation. Its just stupid to put the bar straight on bottom and thats it, if its not an arch than tensile strength is in main role, so just imagine strained rope brigde , it doesn't make sense. It just annoys me that much. Its even posible to put flat bar above wire rope before pouring concrete and prestress it for even better results
Miro, You are describing prestressed concrete. It is a great tool and many people use it and you can do parabolic shaped strand in those systems. This is not economical to do in non prestressed applications and it is actually very expensive and dangerous to do in prestressed beams. It has been done in post tensioned applications in the past but it is very dangerous to construct. Engineering is not about giving the best mathematical answer but it is about giving the best answer given the system that you have to deal with. In my opinion, I think straight bars or tendons are the best solution given the constraints of our system.
@@TylerLey YEs but in prestressed systems wire stands quite loose inside it's lubricated and not catched by concrete at all, so do you think it would be beneficial in non prestressed systems? dont know, i was always about make it perfect first than simplify as much as you can :D btw great videos very informative
One of the best class I miss a lot, Dr. Ley just makes Civil sounds easy. Hope to see Dr. Ley around when I'm back in State!
Thank you so much! I miss you as well but I know I will be back together soon!
I dont really leave comments, but this video made this sooo clear! when you repeat stuff and add sounds really helps me focus! thxs U got a new subscriber!
Simply explained on the theory to better understand. I went to the 9th IVY L school abt 30 years ago. And you are better at explaining and more fun.
To be safe for column design , I would limit the ratio of ultimate axial stress over the F'c to 0.4. This will limit the max. steel bars to abt. 4% and avoid congestion at lappings.
Thank you for the most helpful description of these diagrams!
Thank you for explaining the concrete Interaction diagrams so précised!
Thank you for making this video, this inspires me to create more structural engineering videos to share.
Thanks for your great explanation 👍
the best teachers I've ever met .
Hi Dr. Tyler. This is brilliant- you explained it so simple and straight forward. Any chance you can do a video on a Pushover analysis? In fact any videos available on bridges will be awesome
Excellent work Tyler and thanks👍
Thanks alot sir
It helped me alot
Kindly keep uploading more useful videos like this
I love concrete design
U make me like it more
Good luck
That is really cool. Thank you!
Thank you for making this video.
Thanks for watching and commenting😀
So, um, where is the neutral axis for the point of pure compression or tension? Is it at infinity or the edge of the cross-section?
What a great explanation!
loved it, fantastic! thank you
Looking forward to the design problem.
Shooting it today!
I see it this way - if you design something then the best option would be to design it for a controlled failure. Imagine a bridge - if the ramp to the bridge fails at a lower load than the bridge, then the result would be less severe, especially if the design just causes a minor depression at a safe distance from the bridge.
It could also serve as an indicator for maintenance where when some insignificant part breaks it's a sign that the structure has aged to a certain level and needs an overhaul. So sometimes failure is an option.
I think these are all awesome ideas. Thanks for adding cool comments to this video and lots of other ones. I really appreciate it!
absolutely brilliant thank you
Dr Ley thank you so much for this informative video. Really filled in a knowledge gap I was trying to fill. The Four Critical Points: are we supposed to design the column based on these 4 cases?
We must ensure that the column has enough capacity to fulfill the 4 cases?
Great video Tayler!! Is Clarifyer, or whatever you should be said.
Thanks so much!!!
I had earphones on...my heart skipped a beat at 6.24....🤣🤣🤣
Thank you!
Hi. Do you have interaction diagrams for steel frames?
Well explained wow
I love you enthusiasm
Thanks !
Beyond the lines, the possibility and probability of failure is higher? Since FOS is reduced!
Thank you very much sir
Good video
Nice one
Hats off sir
I think I need an intro to this intro.
Thanks you for made this video
Can you explained Equivalent frame method (EFM) by
Column Analogy Method
Not from table
thanks
Do you mean phi for concrete or phi for the steel? Canadian code has phi=0.65 for concrete and phi=0.85 for steel. This is much simpler and gives practical results. I can see phi jumping to 0.7 for the concrete in the ductile zone and phi for steel jumping to 0.9 but I think that needs to be more clear.
Ty
Thanks!!!
bro the loud noise shook me
Amazing!!
Thanks!
Actually it is Sigma y [N/mm^2]= My [N*mm]*z [mm]/Iy [mm^4] at 0:28. Or Sigma y=My/Wy. @1:04 you just cannot sum or subtract N/mm^2 with N/mm^3. Nice explanations anyway!
man! he is so cool ;)
Why we only consider Compressive stress and Bending stress as a Combined stress ?
Why don't we consider Shear stress in it ?
Just only two stress in structure work in the difference way namely normal stress and shear stress. axial,bending are normal stress can be compression or tension or combination of them.
the beams and walls consider shear stress
We need to find a formulation to relate moment/axialload and shear first to do this !
Plz include stress and crack check .
Excelent class Dr. Ley. Greetings from Ecuador
but what if we had more reinforcment !? not only 4 bars
What can I say in one word about this video/channel... "Best"
I really appreciate the encouragement.
:D perfect
😂😂😂😂 والله عمده يحط عليك المفروض نترجمله السكاشن والله عشان تتعلموا منه
Trigger warning at 6:24
I'm from Bangladesh
Dude sounds just like Saul Goodman
I will never understand why modern engineering is using straight bars in beams, its more logical to use steel wire rope , atleast add it in the middle, pour concrete over it while its loose in curved hanging shape, and under heavy pressure load will be eaqualy distributed, it simulates curved shape of a bar in failure, so the whole beam elastic deformation part is just skipped, result is when it fails it just snaps and thats it, without any cracks or curving deformation. Its just stupid to put the bar straight on bottom and thats it, if its not an arch than tensile strength is in main role, so just imagine strained rope brigde , it doesn't make sense. It just annoys me that much. Its even posible to put flat bar above wire rope before pouring concrete and prestress it for even better results
Miro,
You are describing prestressed concrete. It is a great tool and many people use it and you can do parabolic shaped strand in those systems. This is not economical to do in non prestressed applications and it is actually very expensive and dangerous to do in prestressed beams. It has been done in post tensioned applications in the past but it is very dangerous to construct.
Engineering is not about giving the best mathematical answer but it is about giving the best answer given the system that you have to deal with. In my opinion, I think straight bars or tendons are the best solution given the constraints of our system.
@@TylerLey YEs but in prestressed systems wire stands quite loose inside it's lubricated and not catched by concrete at all, so do you think it would be beneficial in non prestressed systems? dont know, i was always about make it perfect first than simplify as much as you can :D btw great videos very informative