Some civil engineers in the field right now may have thought at least once in their lifetime that cement and concrete are just the same. It only takes one course or subject to turn that myth around, and maybe this article for the layman and other engineers who falsely interchange the two. Both terms are not really engineering jargons as they are widely used in everyday conversations, so let this be settled once and for all.
What is cement? How is it different from concrete?
Cement is a very fine powder made by grinding calcined limestone. It contains mostly calcium and silicon. Cement is the binding agent, or binder, that holds the concrete together.
On the other hand, concrete is a heterogeneous mixture of cement, sand, crushed stone and water. The aggregates, which are the sand and crushed stone, give concrete the mass, while the water activates the cement holding it all together. Different strengths of concrete can be attained out of different ratios of the materials; and when steel is added, it is called reinforced concrete.
By now, there should already be clarity: cement and concrete are two different but related products. Concrete cannot be made without cement, but cement can be made without concrete.
One cannot say that a road is already cemented because that’s a technically incorrect statement. Civil engineers nearby will find it ridiculous to eavesdrop that a road is made just out of powder. Instead, say that the road is already concreted.