What is the Difference Between Concrete and Cement?
People often confuse concrete and cement. Cement is actually an ingredient in concrete that glues together the rock or gravel with the sand, water, and other additives. When a concrete truck is seen driving down the road, it contains ready mixed concrete, meaning a mixture of materials forming concrete. Is the concrete in sidewalks the same as the concrete in bridges? Concrete can be made thousands of different ways. Numerous types sizes and colors of sand, rock, gravel, cements, and chemicals can make today’s concrete do almost anything, from holding up a skyscraper to filling a hole in the ground. Concrete can be made of varying strengths, densities, colors, and characteristics, each serving varying purposes.
While the terms are sometimes used interchangeably, concrete and cement are not the same. Concrete is a building material, a composite of aggregates including sand and gravel, plus cement, water, and other materials. Cement is a key ingredient of concrete, typically making up 10% to 12% of the volume.
The difference between concrete and cement is that concrete contains cement plus sand and gravel. It is the cement that binds the sand and gravel or crushed rock together to form what we call concrete. Concrete then, is more than just cement. Cement is made from limestone, calcium, silicon, iron and aluminum, plus lesser amounts of other ingredients. This mixture is heated in large kilns to about 2,700 degrees Fahrenheit (1,482 degrees Celsius) to form a product called clinkers, which roughly resemble marbles. These are ground to a powder and gypsum is added, creating the gray flour-like substance known as cement. When water is added to cement, a chemical process occurs as it hydrates, allowing it to harden. Cement was a building material of both the Greeks and the Romans, but when Rome fell the widespread use of cement was lost for hundreds of years. Then in the 1700’s Joseph Aspdin, a British citizen, discovered that if he added clay to limestone then superheated it, the resulting mi
You probably use the terms interchangeably, but “concrete” and “cement” do not mean the same thing. Cement is one of the ingredients that makes concrete. The other ingredients are air, water, fine sand, and gravel or crushed stone. Through a process called “hydration,” the mixture hardens—and continues to harden for years after it’s dry. It’s not accurate, then, to call your sidewalk, patio or block walls “cement.” They’re concrete. Another term you might use during a conversation about concrete is “masonry.” Masonry is an umbrella term that covers all building materials that you would typically bind together with mortar, like concrete blocks, adobe, stone and brick.
