## ONE WAY SHEAR DESIGN

## ONE WAY SHEAR DESIGN

(OP)

Hi,

I am using a finite element software to design a slab/raft foundation for one way shear.

I am trying to use shear force(T/m)/shear stress results to do my design.for beams we had learned that we consider the total shear force of the whole section,but we didn't learn for a slab/raft how to design them.

I am taking the average shear force for each 1m width in the slab/raft and provide for it shear reinforcement if needed.Am I right?

I am using a finite element software to design a slab/raft foundation for one way shear.

I am trying to use shear force(T/m)/shear stress results to do my design.for beams we had learned that we consider the total shear force of the whole section,but we didn't learn for a slab/raft how to design them.

I am taking the average shear force for each 1m width in the slab/raft and provide for it shear reinforcement if needed.Am I right?

## RE: ONE WAY SHEAR DESIGN

## RE: ONE WAY SHEAR DESIGN

The finite element programs gives shear force per meter length in a specific vertical plane.

When I choose a vertical plane parallel to a wall for example, I get shear forces per meter length on each node of the plane. If I sum the forces over the whole plane I would have the shear V in T similarly to that of a beam.

The thing is that I get areas on the planes where there is little shear force(T/m) resisted by concrete strength so I don't put reinforcement for them. Plus, taking the whole shear force and apply it to the whole width will give me much lesser reinforcement, by that much lesser reinforcement in area where the peak shear force per meter is(where the failure starts to happen). That's why I divide the plane to 1 m width segments and for each I calculate the required shear reinforcement, by using the average shear value x the width of the segment, or to be more conservative, the maximum shear value x width of the segment.

I want to be sure if this is correct. If not how should I check one way shear in slabs and rafts? and how to provide reinforcement?

## RE: ONE WAY SHEAR DESIGN

As you've discovered, the trick is determining what an acceptable integration width is for one way shear design. You method sounds reasonable. The method in the link might shave off some effort if you choose to adopt it.

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: ONE WAY SHEAR DESIGN

same element. ")applicable for slabs also?

## RE: ONE WAY SHEAR DESIGN

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.