Concrete Mixes

What Are the Proper Concrete Mix Proportions  

There are only 4 crucial ingredients in concrete, which are aggregate, cement, sand, and water, and each one serves a particular purpose. Understanding the purpose of these is vital in determining what proportions are best in any given situation.



This is an adhesive, and the principal ingredient is calcium oxide. Calcium oxide is a by-product of superheated limestone. Cement also contains iron, silicon, aluminum, and various other secondary ingredients. However, it is the cement that holds the aggregate and sand together once it has cured.

While extremely hard, the strength of cured cement cannot compare to that of sand and rock. And as such, it is the very reason why concrete has weak tensile strength and needs rebar. Torque can very easily break concrete, that is because concrete relies on the cement strength to resist torque.

Also, it is important to remember, that more cement does not constitute greater compressive strength, it just means better adhesion, and the two should never be confused as they are not synonymous.


Washed, crushed rock, which is often mistakenly referred to as gravel, is the component that gives concrete the compressive structural integrity it needs. Concrete has tremendous compressive strength, and the sand and rocks support the concrete when it is compressed.


This is not just the filling agent that removes air pockets and spaces between individual crushed rocks, it too has high compressive strength.


This is what creates the chemical change in the quicklime contained in cement that allows it to adhere to the rock and sand, water will also make concrete more workable, and without it, mixing, forming, and finishing concrete would not be possible.

If you would like to make an appointment to discuss a concrete project, please do not hesitate to contact Affordable Concrete Evansville at (812) 213-7358 now, if you live in the Evansville, IN region.