W/C ratio for Concrete with Dairy Manure exposure

[arh13p]

Most of the concrete manure storage structures designed that I deal with are either vertical walled rectangluar shaped or sloped side lagoons. For structures that are intended to be liquid tight, is requiring a w/c ratio of 0.45 still too high? Even though I am located in the US, I have read that Ontario's specification for reinforced concrete structures exposed to "moderate to severe manure" is 0.45 however for "severe" it is 0.40. How do I differentiate what is moderate-severe" and "severe?

Also, for liners on a sideslope (typically 3:1 and 2:1) that will not be subject to any loading (driving) other then the weight of manure, would this be considered "structural concrete" and should the same design basis for liquid tightness be followed as I would for vertical walls?

Thanks,

 

[ishvaaag]

Just a guess, in EHE there is a table for weak, moderate and severe CHEMICAL exposure. I attach it. 2nd column is moderate exposure and 3d column severe exposure.

This is from the concrete structural code in Spain, look in Canada's for the same, or maybe some othe code; ask the client if he knows how to differentiate the aggressivity.

Respect the second question, since the pond will induce stress changes in the vase, from a modern viewpoint is to be considered structural; in the past maybe some of these were let go as constructive concrete because they were sometimes if not most without structural design.

 

[dik]

See if this loads...