Corbel Reinforcement 1

[doka1]

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1659814414/tips/Corbel_Detail_iuforr.pdf[/url]Does it matter if the main reinforcement of a column corbel turns up into the column vs down into the column as usually shown? Closed ties and framing bars are installed as usual.

 

[doka1]

I thought this was a legitimate question. No one willing to weigh in?

 

[Tomfh]

Read the Retaining wall thread:

https://www.eng-tips.com/viewthread.cfm?qid=496756

Similar thing.

 

[doka1]

Thanks for the reply! I wasn’t sure if my case was different because the column is so wide and the main corbel bars have a great deal of length to develop. Also, since the column is in compression wouldn’t that help? The column is also heavily reinforced, and the corbel is being poured monolithic of course.

 

[dik]

I didn't have an answer and I was hoping someone else had one. I thought that maybe distributing the forces over a greater area and reducing the congestion of the reiforcing would likely make the connection better. I couldn't visualise how the compression forces were improving the development of the reinforcing.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[bugbus]

After seeing the recent retaining wall thread that Tomfh linked, I'm now converted into the camp of turning the bars into the compression zone (or toe of footing).

Depending on how hard those main corbel bars are working, it could work though.

 

[dik]

Welcome to the camp... been doing that for nearly 40 years, now... it's the way I was shown... way back when. An engineer at RJC explainted why.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[BridgeSmith]

For the corbels on bridge abutments that support approach slabs, they're always turned down, just as shown in bottom diagram. As with the retaining wall, the hooks/extensions are developed into the compression zone. Do they need to be? Maybe, maybe not; the internal stresses are very complicated, and the distribution of forces through concrete is difficult to model accurately, even with the best FEA. The only thing I think we can be confident of, is that bending it down is better. How much is hard to say, but why make a weaker connection, if you can avoid it?

Rod Smith, P.E., The artist formerly known as HotRod10

 

[dik]

Thanks, Rod... when it was mentioned that they should turn the direction of the compressive force, it made immediate sense. Prior to that, I'd turned them out... at that time I'd only been playing engineer for a few years.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik