Concrete Deflections - Gross, Cracked and Effective Moment of Inertia Explained

In this video, we cover a problem on the immediate deflection of reinforced concrete members, and go over step by step what the terms gross, cracked and effective moment of inertia mean. This is typically a problem that isn't explained well in lectures and we feel that it's important
See a solved step by step example here: • Maximum Immediate Crac...
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[@AFMathandEngineering]

Hope you enjoyed this! Want to see a particular video about reinforced concrete? Let us know in the comments down below!
Link to part 2: ruclips.net/video/67BJTHD-XzI/видео.html

[@dhuvgoku]

Where can i find the part 2? please reup or upload the same. thanks :)

[@AFMathandEngineering]

Coming shortly! Keep notifications on to get updated :D

[@dhuvgoku]

@@AFMathandEngineering Thank you :)

[@dangelocaloggero6566]

You are indeed a great teacher! keep up the good work!

[@brendenmonahan99]

Well done! I was struggling to figure out what Ig was in ACI 318. This was very helpful. Thank you!

[@GenaEnSamIAm]

Thank you for the video man!

[@user-gn1us7mw3n]

Thanks

[@rxi99]

any updates on the long term deflection?

[@indianbudgetguide5207]

Which one should used analysis

[@juanbrnal95]

What about Prestressed Concrete ? Works in the same way ?

[@joseh7612]

i cant really decipher the I_cr equation. is that an exponent of "2", where b and y are being divided by 3?

[@Moseidon502]

How about cracked moment for hollow section ?

[@ettohimpe4313]

Do you have a source where i can find some of the figures you used for my paper?

[@AFMathandEngineering]

Reinforced concrete design by james macgregor is an excellent concrete textbook for reference.

[@bikalshakya]

Why are we using fr*, and not just fr? Where does the code tell us to do this?

[@aloksharma9093]

I think, mathematically the depth of neutral axis is not variable for the cracked section. The need of effective moment of inertia should have a different explanation. Can anyone give the explanation please?
Great video by the way.

[@AFMathandEngineering]

The effective moment of inertia is a replacement for a variable depth of neutral axis. It's kind of an average between gross and cracked as calculating the moment of inertia at small intervals throughout the beam would be ridiculous for every day calculations.

[@WordsandNumbers1]

@@AFMathandEngineering yes.
Multiple sections are cracked after loading and the moment of inertia is Ic for such sections but in between the cracked sections there is Ig. So for calculation of deflection, we try to take a kind of average moment of inertia Ieff that would work equivalently for the whole span.
👍

[@bravek9881]

LIKE LIKE LIKE!👍👍

[@AFMathandEngineering]

Brave K awesome, glad you enjoyed!

[@marcosaparicio4863]

5

[@scotthansson6490]

Please use better pen. It is too thick and symbols get sloppy. Otherwise, great video.

[@fidelespiritu2110]

informative...but pls make a clearer presentation or at least write as clear (scribbles' a bit difficult to decipher)