Concrete water tank design

[Abdel22]

anyone with guidance of how wall going to be connected at corner .....any special reinforcement.

i design retaining wall with 90 on corner. just want see if i have to add any reinforcement at corner.

thanks

 

[Agent666]

How thick are the walls? With thinner walls that cannot anchor standard hooks I've seen diagonal bars across the corner in plan, and sometimes a fillet in the internal face to deal with the corner opening forces. If you do a strut and tie it should be fairly clear where you need reinforcement.

 

[Abdel22]

the wall is 1 foot thick

 

[Agent666]

At that thickness I'd imagine you could anchor bars using standard hooks. You'll no doubt be governed by serviceability crack control criteria so tank doesn't leak, so you should have low enough bar stresses at ultimate limit state. Notwithstanding this the diagonal bar is obviously superior but takes a bit more work. There are a couple of pictures in one of kootk's posts in this thread that show the two corner detail options and discusses many other elements regarding the opening joint detailing and design, albeit in the context of a retaining wall. But not fundamentally different to a corner detail in a tank, you'll also have the same detailing issues at the base to wall connection.

 

[hokie66]

Overlapping U-bars at the corners have been shown to be more efficient in developing the opening bending moments in horizontally spanning walls.

 

[Abdel22]

thank you.

i m working on retaining wall that have a 90 degree angle on corner, just thought it will be same issue as concrete water tank

how about the footing of retaining wall....does it need any special reinforcement at corner too

 

[Abdel22]

 

[Agent666]

I'd say you have the same general issues going on retaining wall vs tank.

But this scenario is also probably more regularly ignored in practice with retaining walls and vertically spanning wall segments are all that's designed and overturning at corners with return wall is argued that it must be better (for overturning). Wall horizontal reinforcement can yield and redistribute horizontally spanning actions to vertical span such that behaviour is closer to an isolated vertical spanning wall with little impact on stability.

If wall was internal to building on inside face then I'd maybe look in a bit more detail due to being an internal space.

 

[Agent666]

For footing I'd simply carry through what reinforcing I could and terminate or start new reinforcement as required. I wouldn't crank reinforcement round bends per say, more an overlap of cages.

 

[Abdel22]

the wall is for a loading dock....retain earth and slab on top,,,,that way they can push stuff to bin on other side of wall.
i design it independently, but i want make sure i provide all reinforcement needed for construction
i never come across wall with 90 corner in construction,,,to get a clear idea how they handle it in construction

thank you