Intro to Interaction Diagrams for Concrete Columns | Reinforced Concrete Column Design

This videos gives an introduction to reinforced column design by using interaction diagrams. These figures are critical for the design of reinforced concrete columns and they can be confusing. This video breaks down the pieces of an interaction diagram and makes it easy to follow and understand. This video also sets the stage for future example problems of using interaction diagrams.

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A huge thanks to Hailey Goodale, my director of awesome, for editing this video.

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[waishengchew]

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!

[gabigomez]

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!

[yikee]

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.

[janlhesternavasca]

Thank you for making this video, this inspires me to create more structural engineering videos to share.

[scottroberts]

Thank you for the most helpful description of these diagrams!

[khalifadaba]

Thanks for your great explanation 👍
the best teachers I've ever met .

[ehinspections]

Thank you for explaining the concrete Interaction diagrams so précised!

[civiltechtime]

Thanks alot sir
It helped me alot
Kindly keep uploading more useful videos like this

[susancloete]

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

[mohamedsaady]

I love concrete design
U make me like it more
Good luck

[HaiLe-jqgo]

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?

[shakti_]

Hi. Do you have interaction diagrams for steel frames?

[ehsnils]

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.

[MrGRsir]

Looking forward to the design problem.

[aymanraouf]

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?

[yikee]

Beyond the lines, the possibility and probability of failure is higher? Since FOS is reduced!

[josemariadiazlopez]

Great video Tayler!! Is Clarifyer, or whatever you should be said.

[davidfernandoaguirretapia]

Excelent class Dr. Ley. Greetings from Ecuador

[shriya]

I had earphones on...my heart skipped a beat at 6.24....🤣🤣🤣

[yodaiam]

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.