How to find the thickness of these walls?
How to find the thickness of these walls?
(OP)
I have this little concrete piece attached to a vertical wall, for which I need to find the thickness "t", which is the same for all the walls that make up the highlighted structure:

The only information I have is the moment and normal force that it will have to carry, and that the reinforcement will have to be approximately similar to a fixed cantilever beam:

To find thickness of walls, where should I start? Should I find the necessary reinforcement to carry the load, and then adjust the thickness of the walls accordingly so that the reinforcement fits? Are there any examples of this, because I could not find it online. It does not have to be exact, I can do with a rough estimate.

The only information I have is the moment and normal force that it will have to carry, and that the reinforcement will have to be approximately similar to a fixed cantilever beam:

To find thickness of walls, where should I start? Should I find the necessary reinforcement to carry the load, and then adjust the thickness of the walls accordingly so that the reinforcement fits? Are there any examples of this, because I could not find it online. It does not have to be exact, I can do with a rough estimate.
RE: How to find the thickness of these walls?
Assuming it's not small, I'd start with whatever thickness is required to fit the reinforcement in there. That's probably in the ballpark of 8 in. thick, but you need to sketch it out for your bar sizes, spacing, and clear cover.
RE: How to find the thickness of these walls?
I was thinking of just finding previous hand calculation examples on concrete corbel design to find necessary reinforcement and then find thickness of walls.
RE: How to find the thickness of these walls?
1. Why are you making a concrete corbel that is hollow? Make it solid - there is no point in attempting to save material when using a strut-and-tie model, since it will only complicate the calculation and still not guarantee that excess deflection of the "corbel walls" does not occur.
2. Why have you drawn a moment in the loading diagram? The load from a part placed on top of the corbel will be vertical and horizontal force, i.e., normal force and shear force, from the deadweight of the structure and the (code-specific) minimum horizontal progressive collapse tie force, respectively. These force components may be designed against using the strut-and-tie models for corbels found in the literature.
Remember that external moments and internal moments are not the same thing.
PS. If this corbel is supposed to carry some type of crane (you mentioned that in another post in this forum earleir this week), you may also consider making the connection a steel structure that is bolted into the wall. Tall and heavy cranes are most often carried by a braced steel frame, and not by concrete walls.
RE: How to find the thickness of these walls?
And these loads have to be inserted into the structure seen in the first drawing, so I need to find a wall thickness big enough to carry this moment and normal force. The way I was thinking of doing it is to find whatever thickness is required to fit the reinforcement in there, and then make it slightly thicker just to be safe.
RE: How to find the thickness of these walls?
RE: How to find the thickness of these walls?
RE: How to find the thickness of these walls?
RE: How to find the thickness of these walls?
RE: How to find the thickness of these walls?
RE: How to find the thickness of these walls?
RE: How to find the thickness of these walls?
I suggest that you do not model anything in an FEA programme before you learn the fundamentals.
RE: How to find the thickness of these walls?
Assuming its all reinforced concrete, make the whole thing solid and design it as a normal corbel of which there are countless design examples within textbooks.
“No engineer shall be more clever than is necessary!”
RE: How to find the thickness of these walls?
(That said with a post history like THIS I state to think he is a student pretending to be an actual engineer.)
RE: How to find the thickness of these walls?
Thank you, it made no sense when I looked at it in my FE model. I think regular concrete corbel design is the way to go.