Problem getting reinforcement output as pier.

[eduardo11791]

Hi all!

Before all, thanks for any response on this, since this is an important proyect and I need some help on how to tackle this. I want to design a concrete wall 1 floor house, and while learning how to design the pier reinforcement, I got a problem:

As shown on picture, this is the geometry that predominates, with inclined top:

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Now, on analysis, it shows the moment diagram inclined too, which It might make sense since the geometry isn't rectangular as shown on the pic:

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Now when I select the design parameters as Concrete cover, maximun bar diameter, I select uniform reinforcing as the type of design:

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When I get the results, this is the visual output:

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Now, I assume that I might not know my concepts in pier and spandrel design in ETABS correctly. But aren't pier design supposed to get the reinforcement at top and bottom since my walls will support the roof load?

Also worth noticing, when I do the spandrel design, the top section gives me a correct area of steel.Any clarification on this will help me out a lot. Thanks.

 

[bowlingdanish]

I would think it has something to do with a non rectangular pier. ETABS doesn't like anything that isn't square and simple and on the same level.

But why are you even using ETABS for this? It's a 1 story building with a lot of concrete walls. If you do the analysis properly in ETABS it will just tell you that you need minimum reinforcement. Perhaps the external walls might need 2 faces of reinforcement for out of plane wind loads, but again do this by hand not in ETABS.

 

[saadpervez1]

ETABS does not calculate non-rectangular piers. Spandrel design is along a particular plane so there will be no problem in that. You need to mesh that area and keep the triangular part separate.