Large Reinforced Concrete Beams Discussion

[CJLCivilStruct]

Hello all,

I'm an avid Linkedin doom scroller of all things engineering (sad, I know..). Just wondering what other Engineers thoughts are on the below with more experience in larger (and taller) projects than I?

Background - Steel fixer posting pictures of pre-fixed cages for a high rise project with large amounts of reinforcement. I'd rather not post the image as I don't want this to sound like an attack on a particular design that I've had no involvement with or know any of the project history.

The beams looked to be in the order of 1.4m deep and 0.8m wide with 5 layers of 5 No. H40 in the tension face and varying reinforcement in compression face. Looked to be highly congested to the point of wondering where there's room for concrete!

I think I would be less shocked if this was a singular transfer beam but from what I could tell this was typical reinforcement across the full beam grid on that particular floor.

It led me to the question, at what point in beam sizing and specifying reinforcement quantities would you begin to question that the concept design of the scheme is less than ideal? Does the reinforcement described above sound typical for these types of projects?

 

[Just Some Nerd]

Nothing stands out to me other than the choice for the beams to be narrow. A wider beam would do the same job with less layers of reinforcement (literally just spreading out the bars more), but maybe there's spatial limitations to why. I've designed 1.4m deep beams before, but they were far wider than they were deep and still needed 3 layers at times.

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Why yes, I do in fact have no idea what I'm talking about

 

[CJLCivilStruct]

Thanks for the response. Yes I feel like one of the reasons it looked 'wrong' was more the congestion of reinforcement rather that the overall dimensions. Appreciate the insight.