is the following mixture respect the europeans standards?
cement => 1 part
sand => 3 parts
water => 1/2 part
According to EN 196, a standard mortar mix for testing cement typically has a cement to sand ratio of 1:3 by weight, with a water-cement ratio that gives a flow of 110±5 mm using the flow table test.
Mortar used in actual construction applications often has a cement to sand ratio ranging from 1:3 to 1:5, with the water content adjusted to achieve the desired workability. The actual mix will depend on factors like the type and grade of cement, the type of sand, the intended use of the mortar, and environmental conditions.
No, in EN 196 the water to binder ratio is fixed at 0.5, irrespective of the flow that you get. The proportions given in the original question are correct. You are allowed to use superplasticizers to compensate if you're using, for example, a cement with high water demand.
What is described above is the ASTM (C109/C109m) approach to standard mortar testing, where you aim for a uniform consistency in the flow table rather than a fixed water to cement (or binder) ratio. Which approach is better or worse is a completely different (and sort of endless) discussion that is still ongoing, but those are the two main trends.
Dear Dr Franco Zunino
The fixed w/c ratio seems to be good since for assessment (flow and compressive strength) of any SCM added to the mortar, this parameter must be kept constant.
Whereas, the ASTM C109 approach is also justifiable since most of the SCM powder remain unhydrated due to insufficient water. Therefore, same flow of 110+-5 (consistency) will make sure to fully hydrate the SCM powder.
I really like your last comment (and sort of endless discussion), and want to be part of this endless discussion in future, to learn for a better and sustainable concrete.
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