Abrams' law (also called Abrams' water-cement ratio law)
is a concept in
civil engineering
Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewa ...
. The law states the strength of a
concrete mix is inversely related to the
mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different eleme ...
ratio
In mathematics, a ratio shows how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemons is eight to six (that is, 8:6, which is equivalent to the ...
of
water
Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...
to
cement
A cement is a binder, a chemical substance used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel ( aggregate) together. Cement mi ...
.
As the water content increases, the strength of concrete decreases.
Abrams’ law is a special case of a general rule formulated empirically by Feret:
:
where
:S is the strength of concrete
:A and B are constants and A=96 N/mm2, B=7 (this is valid for the strength of concrete at the age of 28 days)
:w/c is the
water–cement ratio
The water–cement ratio (w/c ratio, or water-to-cement ratio, sometimes also called the Water-Cement Factor, ) is the ratio of the mass of water () to the mass of cement () used in a concrete mix:
:f = \frac = \frac
The typical values of this ...
, which varies from 0.3 to 1.20
References
[Abrams law, air and high water-to-cement ratios by ELSEVIER ]
Civil engineering
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