Portland cement concrete is the mass formed by mixing Portland cement,
sand, gravel (or particles of other suitable materials), and water.
The quality of concrete may be made to conform to certain requirements
which vary with the purpose of the structure in which the material is
to be used; economy, strength, water-tightness, fire resistance, or
resistance to wear and shock may be the chief requisite. The character
of the constituent materials, the proportions in which they are used,
the consistency, the method of mixing, and the placing and curing of the
concrete are important factors in securing the desired qualities of the
finished product.
Total failure or a product which does not give the service expected
is often the result of the nonobservance of practices recognized as
necessary in the preparation and use of concrete. This bulletin is
intended to assist the inexperienced in making and using concrete
suitable for general farm construction and is confined to a discussion of
the rudiments of plain (not reinforced) concrete work.