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RC moment frame - REINFORCEMENT?

RC moment frame - REINFORCEMENT?

RC moment frame - REINFORCEMENT?

I m designing RC frame (one storey). It is a moment frame so column - beam reinforcement details are important.
I have to draw reinforcement details for column - beam connection and Im kinda lost - im doing this for the 1st time and I dont have any examples.

Should I leave straight reinforcement from the columns and bent beam rebars at the end and connect them to column rebars (case 1)?
or should I bent column rebars at the top into the beam (case 2) and leave beam reabars straight?
or should I do combination of both cases?

I also dont know what to do with each rebar at the top of a column since there are so many of them. If there was another storey above Id leave column rebars straight, but since I have one storey, i m not sure.

I m also not sure how to do this since its a 3d frame. I have another beam from other direction too. so im confused which rebars to bent.

What is the most sufficient and simple way to go there? Any detail, photo would be great...

RE: RC moment frame - REINFORCEMENT?

- I try to avoid having to field bend the column bars as it's a hassle in the field.

- I try to avoid having beam bars cast into the column as that's a pain in the field.

- May need some vertical u-bar ties coming down from the top of the beam.

- Get yourself a copy of this: 352R-02

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: RC moment frame - REINFORCEMENT?

Try to make your beam wider than your column dimensions; if you can make your beam width 400. It helps with placement. Your column bars should hook into the beam, but, the hooks should be at the top of the beam. Your beam bottom steel can hook upwards or sideways, but again, the bar should extend to the outside face of the beam/column. Your top steel should hook downwards into your beam or sideways and also extend to the far face. I loaded a cad drawing showing column bar placement on to the site... you should be able to dig up a copy.

Do a quick detail showing bar placement to avoid conflicts. Draw the bars with the correct hook bending radius, too. [italics-added to original post]


RE: RC moment frame - REINFORCEMENT?

Related but not exactly the same, there was a significant discussion on detailing cantilever retaining walls here thread507-401855: Retaining Wall - Flexural Reinforcement from Stem Into Footing

Just bending the bars around the corner will not get you exactly what you're after. Take a close look at how the stresses try to transfer across the joint. Do some research into opening and closing joints in concrete.

RE: RC moment frame - REINFORCEMENT?

thanks for help!

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