What’s the Difference Between Concrete and Cement?
If you start a project that involves a hard, paved surface—like a sidewalk or a driveway—given you are going to use concrete forms but are you going to use concrete or cement to get the job done? To a novice builder, this may seem like a redundant question. After all, aren’t they pretty much the same thing? As a matter of fact: no, they’re not. Despite being used interchangeably, the difference between cement and concrete is an important one to keep in mind. They are two different materials with similar but also vastly different properties, and knowing the difference between one and the other could save you a major headache once you actually begin your project.
Concrete vs. Cement
To put it simply: concrete is a composite while cement is an ingredient. Concrete is made up of several different materials—one of which is cement—and is everywhere. Cement is a binding agent that can be used on its own but is done so pretty infrequently. In fact, the trucks we often label “cement trucks” are, in reality, filled with concrete.
Depending on your project, it may be wiser to use one over the other. Before you can determine which one to use, however, it’s important to know how each one behaves.
Concrete is a tough, long-lasting building material, and it is used practically everywhere. Over 5,000 years ago, the Egyptians began building pyramids with a sort of proto-concrete. They made bricks out of a mixture of mud and straw, and mortars form gypsum and lime. More advanced concrete constructions were made by the Roman Empire using a concrete mix of quicklime, pozzolana, and pumice. Cement, aggregates, and admixtures are the main components of modern concrete, with cement making up about 10-15% of concrete’s composition.
Hardened concrete has a high compressive strength and is rot and corrosion-resistant. It also has the unique property of getting stronger as time goes on and will continue building strength for years after the project is complete. However, it has a poor tensile strength, which means it will fracture when stretched. Steel beams can be inserted in concrete to make reinforced concrete, giving it that missing tensile strength. This is why you might see road bridges starting off as large steel frames before the concrete is poured in—it’s not just a placeholder. Think of it like your body: your muscles are very strong and can withstand a lot of weight, but they would collapse during movement if it weren’t for your skeleton.
Applications of Concrete
Concrete is used by many industry professionals to construct apartments, bridges, foundations, and a variety of other structures, but you don’t need a hard hat and reflective vest to work effectively with it. Landscape detailing, fence construction, and front sidewalks are just some of the DIY tasks that amateur handymen utilize them for.
However, there are some smaller projects where the coarse aggregates in concrete may make it unsuitable for the job. Fine aggregate is mixed with cement and water for smaller applications where coarse aggregate is impractical. This product is known as mortar and is commonly used in bricklaying. A grout is a mortar that has been made more malleable or fluid, and it can be found holding tile flooring together in homes across America.
Cement is, as stated before, a binding ingredient in concrete. Without cement, concrete wouldn’t hold together nearly as well as it does. Unlike concrete, cement sometimes occurs in nature. Deposits of a natural form of cement have been found in Israel, the oldest of which dates back to 12,000,000 BC. However, most cement used in construction are man-made and commonly based on lime or calcium silicate. They’re classified as non-hydraulic or hydraulic, depending on their ability to set in the presence of water, and the most common type of cement used today is Portland cement—a type of hydraulic cement made with limestone, clay, shale, marl, chalk, bauxite, iron ore, and sand.
Though it is a major ingredient in concrete and the main provider of its strength and stability, cement is not a strong material. On its own, it’s a far more brittle material and is more prone to cracks and wear. Think of it like a papier-mâché sculpture—if you didn’t add some sort of glue to the water, all you would have would be a pile of soggy newspaper. However, the glue on its own probably wouldn’t make a very stable sculpture either.
Applications of Cement
The main difference between cement and concrete is that, apart from binding concrete together, there isn’t much practical use for cement as a standalone construction material. It can be used as a surface material for masonry, giving projects a smoother finish. It can also be used in place of grout or to fill in cracks in worn concrete. Apart from these and a few other small jobs, cement is simply too brittle on its own to be a reliable construction material.
Starting Your Project
Now that you know the difference between cement vs. concrete, you’re ready to start your project. However, it’s not the brightest idea to go into a project involving concrete without a mold or form of some sort to maintain the desired shape of your structure. Concrete may be a durable material, but it needs to be formed tightly onto a shape for maximum durability. Here at Forming America, we have a variety of concrete forms for sale to suit any project you may have. Whether you’re a professional in the field looking to build an office or a DIY beginner just looking to make a nice sidewalk, we can guarantee that our concrete forms will be up to any task.