rectangular tank design and analysis

[daroot]

Question:

I saw this subject discussed on thread507-169608 in Nov 06. I've got a existing rectangular CMU secondary containment system with a long wall length of 35' and a height of 5' that I need to do a structural analysis on. The secondary containment was built as an afterthought for some high pH wastewater.
I'd like to use Bureau of Reclamation EM 27 for the moment analysis, but the a/b ratio is 3.5 (off the charts). The wall sits on a separate foundation and is not not tied to the floor system, so there is no cantilever action.

I'm looking to compute the Mx and My against this wall. Any thoughts?

 

[csd72]

I doubt the horizontal span will take any significant amount of load. Design the vertical cantilever to take all the load and put in some horizontal rebar for shrinkage.

 

[COEngineeer]

Well, your vertical wont do a whole lot if it is not tied properly to the footing (to create cantilever action). So I disagree with csd. I guess you need to know what kind of reinforcement first it has especially the dowel into the footing. how big is the footing? Is it safe to assum the bottom is fully fixed?

Never, but never question engineer's judgement

 

[COEngineeer]

Ooopss.. assuming 4 instead of 7 is not conservative. You need to model it .

Never, but never question engineer's judgement